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112
https://medicalsciences.stackexchange.com/questions/3299/what-is-the-effect-of-smoking-before-or-during-early-pregnancy-on-the-baby
[ { "answer_id": 3434, "body": "<p>While most studies appear to be on women who quit during pregnancy, I found a study that compared pregnancy outcomes in women who never smoked, quit smoking before pregnancy, quit smoking in early pregnancy, and those that smoked during pregnancy. It found </p>\n\n<blockquote>\n <p>maternal smoking cessation <strong>before or during</strong> early pregnancy appears to result in appropriate fetal and childhood growth </p>\n</blockquote>\n\n<p>The whole study <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/18298691\" rel=\"nofollow\">Active and passive maternal smoking during pregnancy and the risks of low birthweight and preterm birth: the Generation R Study</a> is available on the internet and I recommend reading it in full and also looking at the references. The differences in birth weight between the babies born to women who quit before and during early pregnancy were not significant. </p>\n\n<p>Another study in 7000 women in the Netherlands also found no difference between women who didn't smoke and women who quit before 18 weeks of pregnancy. </p>\n\n<blockquote>\n <p><strong>For all active smoking categories in early pregnancy, quitting smoking was associated with a higher birthweight than continuing to smoke.</strong> Tendencies towards smaller non-significant beneficial effects on mean birthweight were found for reducing the number of cigarettes without quitting completely. This study shows that active and passive smoking in late pregnancy are associated with adverse effects on weight and gestational age at birth. <strong>Smoking in early pregnancy only, seems not to affect fetal growth adversely.</strong></p>\n</blockquote>\n\n<p><a href=\"http://www.ncbi.nlm.nih.gov/pubmed/18298691\" rel=\"nofollow\">Active and passive maternal smoking during pregnancy and the risks of low birthweight and preterm birth: the Generation R Study</a></p>\n\n<p>Note that for all of these studies, just reducing the number of cigarettes per day is counted as continuing to smoke. </p>\n", "score": 5 } ]
3,299
CC BY-SA 3.0
What is the effect of smoking before or during early pregnancy on the baby?
[ "smoking", "obstetrics" ]
<p>I assume it will be harmful to the baby if a woman smokes while pregnant. How about the situation where the woman smokes, gets pregnant and then stops? Does the smoking in the period until the pregnancy affect the baby? How long before a pregnancy does a woman need to quit smoking in order to insulate the baby from the negative effects of smoking?</p>
9
https://medicalsciences.stackexchange.com/questions/3302/why-do-80-of-children-with-autism-appear-to-improve-when-they-have-a-fever
[ { "answer_id": 3873, "body": "<p>I could find one letter to the editor from 2011 that posits a few mechanisms by which increased blood flow caused by the fever might make autism symptoms better: <a href=\"http://link.springer.com/article/10.1007%2Fs11065-011-9157-y\" rel=\"nofollow noreferrer\">Does fever relieve autistic behavior by improving brain blood flow?</a>. It also mentions a workshop on the topic that happened in 2010.</p>\n<p>Here is the <a href=\"https://sfari.org/updates-and-events/workshop-reports/2010/workshop-report-fever-and-autism\" rel=\"nofollow noreferrer\">workshop report</a>.</p>\n<blockquote>\n<p>One clear conclusion from the meeting is that much more research is needed to investigate the relationship between fever and autism, in particular whether the fever-related responses are a result of the temperature changes, or of a neuro-immune response related to infection. Clinical tests can examine the role of temperature by monitoring the effect of safely raising temperatures (such as in a water bath) on symptoms</p>\n</blockquote>\n<p>There is a <a href=\"http://link.springer.com/article/10.1007%2Fs11065-011-9159-9\" rel=\"nofollow noreferrer\">reply to the letter to the editor</a> with some more thoughts related to causes.</p>\n<p>I could find nothing newer, but this year, a grant of 900,000 USD grant was awarded to Indiana University to research that link: <a href=\"http://news.indiana.edu/releases/iu/2015/07/autism-fever-study.shtml\" rel=\"nofollow noreferrer\">NIH awards Indiana University $900,000 to study link between body temperature and autism</a></p>\n<blockquote>\n<p>&quot;Like many research topics, the phenomenon isn't totally unknown, but exact mechanisms linking body temperature and autism haven't yet been organized as a principle and unpacked to see how it could work,&quot; said Alberts.</p>\n<p>The IU study will be conducted in mice. Alberts and Harshaw will investigate the association between physiological deficits in the ability to regulate body temperature and social behaviors associated with autism using mouse models for both conditions.</p>\n</blockquote>\n", "score": 4 } ]
3,302
CC BY-SA 3.0
Why do ~80% of children with autism appear to improve when they have a fever?
[ "autism", "fever" ]
<p>I read on this <a href="http://www.webmd.com/brain/autism/news/20071203/report-fever-improves-autism-symptoms" rel="nofollow">WebMD article</a> (published in 2008) that children with autism appear to improve when they have a fever. What could explain it?</p> <p>One hypothesis mentioned in the article is that:</p> <blockquote> <p>fever may affect brain function at the cellular level by influencing the production of immune-system signaling proteins known as cytokines.</p> </blockquote> <p>Is there evidence to support this hypothesis in newer studies?</p>
9
https://medicalsciences.stackexchange.com/questions/3310/is-there-a-cure-for-bad-breath
[ { "answer_id": 5581, "body": "<p>You may actually want to try cutting out the mouthwash. There's some evidence that <a href=\"http://www.newsmax.com/Health/Headline/mouthwash-risk-harm-bad/2014/02/28/id/555321/\" rel=\"nofollow\">the bacteria being killed with frequent use of mouthwash may include the healthy sort that your mouth needs</a>, not to mention that it may dry your mouth out, which will also make your breath worse.</p>\n", "score": 3 }, { "answer_id": 5586, "body": "<p>You might have gum disease (do your gums bleed when flossing?). Go for a checkup with a dentist and ask about a regular or deep cleaning. Usually, a regular cleaning will be done, which will remove most surface bacteria from the gums/teeth. Most people don't know this, but it is important to get regual cleanings by the dentist, at least around once a year. Then the dentist will prescribe a specific antibacterial mouthwash such as perioaid or periogard - it is crucial that you're advised by dentist what specific mouthwash to get and in what concentration. From this point on if you keep up good oral hygiene 99% of problems will be gone.</p>\n\n<p>tldr; get a checkup with a dentist</p>\n", "score": 1 }, { "answer_id": 10671, "body": "<p><a href=\"http://www.dailymail.co.uk/health/article-3173114/Do-bad-breath-licking-spoon-ditching-high-protein-diet-experts-reveal-tell-mints-just-make-problem-WORSE.html\" rel=\"nofollow noreferrer\">A Daily Mail article</a> listed many causes I had not heard about (not a trustworthy reference, but the interviewed experts seem legitimate):</p>\n\n<ul>\n<li>Dieting, especially low-carbohydrate diets </li>\n<li>Intense exercising</li>\n<li>Dehydration </li>\n<li>Skipping breakfast </li>\n<li>Ph balance changes in the mouth</li>\n<li>Caffeine, especially coffee </li>\n<li>Alcohol </li>\n<li>Sugary foods</li>\n<li>Flying on a airplane</li>\n</ul>\n", "score": 0 } ]
3,310
Is there a cure for bad breath?
[ "treatment", "bacteria" ]
<p>I typically wake up with a mouth tasting like something died in it. Throughout the day it continues to taste bad, and I'm told it smells significantly worse. This has gotten to the point that it's getting in the way with relationships.</p> <p>I assume this started during a few-month period of terrible oral hygiene, but since I have greatly improved oral habits, brushing twice daily after meals, flossing and using mouthwash, but the problem continues. Mouthwash alleviates the issue for maybe an hour at a time, and some mouthwashes help for as little as 20 minutes. I've spent a good deal of time googling, and I can't seem to find anything about CURING bad breath by, say, rebalancing oral bacteria. Is there a long-term solution for bad breath, preferably permanent (considering I haven't found anything that works for more than an hour, the standard is pretty low)?</p>
9
https://medicalsciences.stackexchange.com/questions/3439/how-is-alcohol-eliminated-from-breast-milk
[ { "answer_id": 3993, "body": "<p>The best reference I could find on this was <a href=\"http://www.bfr.bund.de/cm/350/alcohol-during-the-nursing-period-a-risk-assessment-under-consideration-of-the-promotion-of-breastfeeding.pdf\" rel=\"noreferrer\">Schwegler et al. (2013)</a>, which gave detailed descriptions of both the processes of transfer of alcohol to the bloodstream and breast milk and the effects thereafter in the mother and the infant.</p>\n<p>Here is a somewhat condensed timeline of what happens.</p>\n<ol>\n<li><p><strong>Intake.</strong> The mother consumes an alcoholic beverage, which travels along the digestive tract from the mouth through the esophagus and into the stomach and intestines.</p>\n</li>\n<li><p><strong>Resorption.</strong> The alcohol (really ethanol, for all intents and purposes) is resorbed in minute quantities in cells in the esophagus, and in moderate amounts in the stomach. Most of the resorption takes place in the intestines and beyond, specifically the smaller intestines, thanks to the &quot;first pass effect&quot;. The ethanol is now transferred to the bloodstream.</p>\n</li>\n<li><p><strong>Breakdown of alcohol.</strong> The ethanol is transformed into metabolite acetaldehyde via alcohol dehydrogenase (ADH). ADH is more common in the liver and intestines than in the stomach, which in part accounts for the higher resorption rates in the lower part of the digestive tract. Next, the acetaldehyde undergoes oxidation by aldehyde dehydrogenase (ALDH) or monooxygenase CYP2E1. The result is acetate, which is then turned into water or carbon dioxide, as normal.</p>\n</li>\n<li><p><strong>Transfer from the bloodstream to breast milk.</strong> This step happens concurrently with (3). Some of the ethanol circulating in the bloodstream is transferred to breast milk along with other substances. This transfer often contains ethanol that has been resorbed from the stomach, where less ethanol is resorbed and filtered away. Additionally, acetaldehyde is generally not present in breast milk (Kesäniemi (1974) is cited on page 16). The reason for this is unknown, but it points to the absence of ADH.</p>\n<p>The upshot of all this is that there may be little to no breakdown of alcohol in breast milk. Breakdown via ADH and ALDH would happen between resorption and transferal/lactation.</p>\n</li>\n</ol>\n<p>Levels of alcohol in the blood and in breast milk are generally the same, thanks to diffusion between the various glands in the breasts and the bloodstream (note that there are, of course, specialized veins and arteries for the mammary glands). Diffusion out and in means that there is not a significant net gain or loss of alcohol from the breast milk.</p>\n<p>One reason for different concentrations in different groups of women depends on how proteins responsible for the filtering and breakdown are released. The authors say (page 16)</p>\n<blockquote>\n<p>To explain the observed differences during lactation, Pepino et al. (2007)\nhypothesised that increased levels of regulatory proteins are released during the breastfeeding phase and that these proteins delay the passage of the alcohol from the stomach to the small intestine and liver, thereby increasing the first pass effect. The findings were confirmed in a further study by Pepino &amp; Mennella (2008) among mothers who pumped off their milk.</p>\n</blockquote>\n<p>It's worth noting that only a small amount of the total amount of alcohol makes its way unfiltered into breast milk. As <a href=\"http://pubs.niaaa.nih.gov/publications/arh25-3/230-234.htm\" rel=\"noreferrer\">Menella (date unknown)</a> writes (emphasis mine),</p>\n<blockquote>\n<p>In general, less than 2 percent of the alcohol dose consumed by the mother reaches her milk and blood. Alcohol is not stored in breast milk, however, but its level parallels that found in the maternal blood. <strong>That means that as long as the mother has substantial blood alcohol levels, the milk also will contain alcohol.</strong></p>\n</blockquote>\n<p>This is the key principle. Basically, there is little to no breakdown of alcohol in the mammary glands, due in part to the lack of ADH. While some enters through the bloodstream, it can diffuse out and be broken up in the normal fashion.</p>\n", "score": 6 } ]
3,439
CC BY-SA 3.0
How is alcohol eliminated from breast milk?
[ "alcohol", "breastfeeding" ]
<p>Searching for whether it is safe to breastfeed after alcohol consumption, I found lots of pages telling me that alcohol concentration in breast milk spikes after consumption, but then decreases again afterwards, same as it does in blood. From the article <a href="http://www.babycenter.com/0_alcohol-and-breastfeeding_3547.bc" rel="nofollow">Alcohol and Breastfeeding</a> from Babycenter.com:</p> <blockquote> <p>Wait at least two hours after you finish a drink before nursing your baby to give your body a chance to clear the alcohol.</p> </blockquote> <p>However, since breast milk does not get continuously filtered by the liver like blood does, it is unclear to me how this works. Is there any scientific literature available for how the process of eliminating alcohol from breast milk works? </p>
9
https://medicalsciences.stackexchange.com/questions/3443/comorbidity-of-autoimmune-diseases
[ { "answer_id": 4061, "body": "<p>Yes, there is statistically significant comorbidity with autoimmune diseases. </p>\n\n<p>The study <a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2783422/\" rel=\"noreferrer\">Recent Insights in the Epidemiology of Autoimmune Diseases: Improved Prevalence Estimates and Understanding of Clustering of Diseases</a> analysed other studies on the subject. It puts the comorbidity of 29 autoimmune diseases - including, for example, Crohn's, diabetes, rheumatoid arthritis - at around 7 to 9 percent. </p>\n\n<p>Earlier studies put the comorbidity number lower, at around 4 to 6 percent, this appears to depend mainly on what diseases are considered and the quality of the records being reviewed for the large population-based studies. </p>\n\n<p>They found that certain diseases \"cluster\" in patients, for example type 1 diabetes, rheumatoid arthritis and thyroiditis. The reverse is true as well, several of the analysed studies report that rheumatoid arthritis in combination with multiple sclerosis occur together less frequently than expected. </p>\n\n<p>Two other main meta analyses on the subject are</p>\n\n<ol>\n<li><a href=\"http://m.aje.oxfordjournals.org/content/169/6/749.full\" rel=\"noreferrer\">Are Individuals With an Autoimmune Disease at Higher Risk of a Second Autoimmune Disorder?</a> in the American Journal of Epidemiology</li>\n<li><a href=\"http://www.ncbi.nlm.nih.gov/pubmed/16477262\" rel=\"noreferrer\">Autoimmune diseases co-occurring within individuals and within families: a systematic review</a> in the journal Epidemiology</li>\n</ol>\n\n<p>The conclusion that a significant comorbidity exists and that it's more prevalent between certain diseases is drawn by all these studies the studies, which is also discussed in the first paper I linked. </p>\n", "score": 5 } ]
3,443
CC BY-SA 3.0
Comorbidity of autoimmune diseases
[ "autoimmune-disease" ]
<p>Do people who have one autoimmune disease (for example rheumatoid arthritis, Crohn's, Hashimoto hypothyroidism) have a statistically significant higher chance of developing another autoimmune disease in another part of their body later in life? </p>
9
https://medicalsciences.stackexchange.com/questions/3579/why-are-peanut-allergies-so-much-more-severe-than-other-food-allergies
[ { "answer_id": 23424, "body": "<p>To start, Peanut allergy is one of the most common allergens in the allergic population with 12 known allergen proteins.</p>\n<blockquote>\n<p>four common food allergy superfamilies: Cupin (Ara h 1), Prolamin (Ara\nh 2, 6, 7, 9), Profilim (Ara h 5), and Bet v-1-related proteins (Ara h\n8). Among these peanut allergens, <strong>Ara h 1, Ara h 2, Ara h 3 and\nAra h 6</strong> are considered to be major allergens which means that they\ntrigger an immunological response in more than 50% of the allergic\npopulation.\nSource: Mueller GA, Maleki SJ, Pedersen LC (2014). &quot;The Molecular Basis of Peanut Allergy&quot;. Current Allergy and Asthma Reports.- <a href=\"https://en.wikipedia.org/wiki/Peanut_allergy\" rel=\"nofollow noreferrer\">wikipedia</a></p>\n</blockquote>\n<p><b></b></p>\n<blockquote>\n<p>Peanuts harbor <strong>12 allergens</strong> and multiple isoforms recognized by the\nAllergen Nomenclature Sub-Committee of... - <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4785306/\" rel=\"nofollow noreferrer\">Molecular basis of peanut allergy</a></p>\n</blockquote>\n<p><em><strong>Comparison</strong></em></p>\n<p>Compared to the other common allergy-causing food are : <strong>Eggs, Milk, Tree nuts, Fish, Shellfish, Wheat and Soy</strong>, which account for 90% (including peanuts) of the total allergic population -\n<a href=\"https://acaai.org/allergies/types/food-allergy\" rel=\"nofollow noreferrer\">American college of allergy, asthma and immunology</a></p>\n<p><b></b></p>\n<blockquote>\n<p><strong>Five major allergenic proteins</strong> from the egg of the domestic chicken\n(Gallus domesticus) have been identified <a href=\"https://en.wikipedia.org/wiki/Egg_allergy\" rel=\"nofollow noreferrer\">wikipedia, egg allergy</a></p>\n</blockquote>\n<p><b></b></p>\n<blockquote>\n<p><strong>Six major allergenic proteins</strong> from cow's milk have been identified <a href=\"https://en.wikipedia.org/wiki/Milk_allergy\" rel=\"nofollow noreferrer\">wikipedia, milk allergy</a></p>\n</blockquote>\n<p><b></b></p>\n<blockquote>\n<p><strong>Tree nuts</strong></p>\n<p>Hazenut: 13 allergen proteins</p>\n<p>Wallnut: 7 allergen proteins</p>\n<p>Pecan: 3</p>\n<p>Almond: 6</p>\n<p>Cashew: 4</p>\n<p>Pistachio: 6</p>\n</blockquote>\n<p><a href=\"https://www.sciencedirect.com/science/article/pii/S0161589018300907\" rel=\"nofollow noreferrer\">Science Direct</a></p>\n<p><b></b></p>\n<blockquote>\n<p>As implied from a long article, <strong>common fish species vary from 1-4 allergens</strong>..\n<a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4001008/\" rel=\"nofollow noreferrer\">NCBI - Fish Allergens at a Glance: Variable Allergenicity of Parvalbumins, the Major Fish Allergens</a></p>\n</blockquote>\n<p><b></b></p>\n<blockquote>\n<p>As implied from a tables in the article, <strong>common shellfish species vary from 1-4 allergens</strong>.. <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5306157/\" rel=\"nofollow noreferrer\">NCBI - Allergens and molecular diagnostics of shellfish allergy</a></p>\n</blockquote>\n<p><b></b></p>\n<blockquote>\n<p>There are <strong>four major classes of seed storage proteins</strong>: albumins, globulins, prolamins and glutelins <a href=\"https://en.wikipedia.org/wiki/Wheat_allergy\" rel=\"nofollow noreferrer\">wikipedia -Wheat allergy</a></p>\n</blockquote>\n<p><b></b></p>\n<blockquote>\n<p>Allergenic proteins from soy are named under a nomenclature decided by\nIUIC, which is also responsible for numbering many of the proteins.\nProteins numbered by IUIC include:[18]</p>\n<p>Gly m 1, a hydrophobic protein Gly m 2, defensin Gly m 3, profilin Gly\nm 4, PR-10 Gly m 5, vicilin, a cupin Gly m 6, legumin, a cupin Gly m\n7, seed biotinylated protein Gly m 8, 2S albumin These proteins are\nrecognized by the immune system as antigens in susceptible\nindividuals. <strong>As many as 8 other soy allergenic proteins are known</strong>. <a href=\"https://en.wikipedia.org/wiki/Soy_allergy\" rel=\"nofollow noreferrer\">wikipedia - Soy allergy</a></p>\n</blockquote>\n<p><em><strong>Conclusion</strong></em></p>\n<p>Since there is no article directly correlating the food and the severity of its allergic reaction. It is safe to say that the number of allergens in the food has a significant relationship to the severity of the allergic reaction.</p>\n<p><em><strong>Notes</strong></em><br />\nthere had been studies regarding the relationship between doses and the reaction but with unpredictable results. Other studies emphasized the risk of doing human studies.</p>\n", "score": 3 } ]
3,579
CC BY-SA 4.0
Why are peanut allergies so much more severe than other food allergies?
[ "immune-system", "allergy", "nuts" ]
<p>Based on my understanding of how adaptive immune responses arise, I would expect peanut allergies to be roughly normally distributed with regard to severity, like other food allergies. However, peanut allergies seem to be at least generally accepted as trending to the "extremely severe" side of the scale.</p> <p>What is it about peanut antigens that promotes the development of extreme allergic responses?</p>
9
https://medicalsciences.stackexchange.com/questions/3646/what-heart-conditions-cause-dizziness-after-during-exercise
[ { "answer_id": 3656, "body": "<p>Dizziness or giddiness during exercise is classically caused by obstruction to the outflow of the heart i.e. aortic stenosis (see <a href=\"https://www.nlm.nih.gov/medlineplus/ency/article/000178.htm\" rel=\"noreferrer\">MedlinePlus</a>). This condition is most commonly seen in either young persons due to bicuspid aortic valve or in elderly with sclerotic aortic valves. In developing countries, it may occur due to rheumatic heart disease also. </p>\n\n<p>When a normal person exercises, extra blood flow is needed in the muscles. Hence, heart starts pumping more blood to keep up with this increased demand of the body. However, in persons with aortic stenosis, orifice of the outlet of the heart is small and fixed. Hence, blood flow (cardiac output) cannot increase when person exercises. Due to blood vessel dilatation in muscles, blood goes preferentially to muscles and flow to the brain gets reduced. Hence giddiness or dizziness occurs. It can progress to syncope, i.e. transient unconsciousness and fall. </p>\n", "score": 5 } ]
3,646
CC BY-SA 3.0
What heart conditions cause dizziness after/during exercise?
[ "blood-pressure", "heart-disease", "exercise" ]
<p>Lots of stuff causes dizziness after/during exercise. But if you Google "<em>dizziness after exercise</em>" you'll get 10,000 articles and lame blogs that are basically just copies of one another that all essentially make the same vague blanket statement:</p> <blockquote> <p><em>In rare cases, <strong>heart conditions</strong> can cause dizziness after/during exercise.</em></p> </blockquote> <p>But, LOL, not a single one of these articles/lame blogs actually deep dives into what <em>specific heart conditions</em> they are referring to.</p> <p>So I ask: <strong>What specific heart conditions would cause dizziness after/during exercise, and why do they make one dizzy?</strong></p>
9
https://medicalsciences.stackexchange.com/questions/3668/how-does-the-stomach-handle-liquid-vs-solid-food
[ { "answer_id": 3807, "body": "<h1>More stuff = More time</h1>\n\n<p>The stomach has <a href=\"https://en.wikipedia.org/wiki/Stomach#Stomach_as_nutrition_sensor\" rel=\"noreferrer\"><strong>sensory capabilities</strong></a> that help determine the nutritional content of what it receives. This allows it to \"taste\" and decide what it needs to add to the \"stirring pot\" to get cooking. When the stomach receives traditional foods like carbohydrates, fats, and proteins, it adds protein-digesting enzymes such as pepsin and hydrochloric acid (HCL) to break down the nutrients for absorption in the intestines. </p>\n\n<p>(This is why we consume <a href=\"http://www.uhs.wisc.edu/health-topics/digestive-system/upset-stomach.shtml\" rel=\"noreferrer\">fluids and light carbs on an upset stomach</a>- we want to prevent the stomach from getting aggravated and overworked or even inflamed.)</p>\n\n<p>The <a href=\"http://scienceline.ucsb.edu/getkey.php?key=275\" rel=\"noreferrer\">more complex the food, the longer it stays in the stomach.</a> So protein can take hours while simple carbohydrates like white bread or sugar could take just half an hour or less. Liquids like tea, juice, and alcohol tend to be even less complicated, water least of all- <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/21997675\" rel=\"noreferrer\">taking possibly just minutes to start</a> passing into the blood stream if there is no food in the stomach and fully entering the blood stream within 1-2 hours.</p>\n\n<p>If there happens to be food already in the stomach, the liquid must wait until the stomach finishes digesting the food to enter the small intestine along with the broken-down food. This is why health centers often advise alcohol consumption with food. <a href=\"http://www.brown.edu/Student_Services/Health_Services/Health_Education/alcohol,_tobacco,_&amp;_other_drugs/alcohol/alcohol_&amp;_your_body.php\" rel=\"noreferrer\">Food will slow the emptying of the stomach into the small intestine, where alcohol absorption is very rapid.</a></p>\n\n<p>References are respective to order of mention.</p>\n\n<ol>\n<li><a href=\"https://en.wikipedia.org/wiki/Stomach#Stomach_as_nutrition_sensor\" rel=\"noreferrer\">https://en.wikipedia.org/wiki/Stomach#Stomach_as_nutrition_sensor</a></li>\n<li><a href=\"http://www.uhs.wisc.edu/health-topics/digestive-system/upset-stomach.shtml\" rel=\"noreferrer\">http://www.uhs.wisc.edu/health-topics/digestive-system/upset-stomach.shtml</a></li>\n<li><a href=\"http://scienceline.ucsb.edu/getkey.php?key=275\" rel=\"noreferrer\">http://scienceline.ucsb.edu/getkey.php?key=275</a></li>\n<li><a href=\"http://www.ncbi.nlm.nih.gov/pubmed/21997675\" rel=\"noreferrer\">http://www.ncbi.nlm.nih.gov/pubmed/21997675</a></li>\n<li><a href=\"http://www.brown.edu/Student_Services/Health_Services/Health_Education/alcohol,_tobacco,_&amp;_other_drugs/alcohol/alcohol_&amp;_your_body.php\" rel=\"noreferrer\">http://www.brown.edu/Student_Services/Health_Services/Health_Education/alcohol,<em>tobacco,</em>&amp;_other_drugs/alcohol/alcohol_&amp;_your_body.php</a></li>\n</ol>\n", "score": 3 } ]
3,668
CC BY-SA 3.0
How does the stomach handle liquid vs solid food?
[ "digestion", "gastroenterology", "stomach" ]
<p>I've read the the stomach must secrete HCl and pepsin to break down food. If I have an empty stomach, then drink a large amount of liquid, I wonder if the liquid passes quickly, or gets processed in the same amount of time as solid food.</p> <p>So how does the stomach handle an environment of pure liquid, versus an environment of solid foods.</p>
9
https://medicalsciences.stackexchange.com/questions/3696/can-crossing-my-eyes-damage-them
[ { "answer_id": 3926, "body": "<p>It is actually a pretty common myth that crossing your eyes too much or for too long will make them get stuck that way. Crossing your eyes does look very similar to <a href=\"https://www.nlm.nih.gov/medlineplus/ency/article/001004.htm\" rel=\"noreferrer\">strabismus</a> which is an actual medical disorder where the eyes are crossed and it does need to be treated. Strabismus is not voluntary, compared to what you are talking about, which is voluntary. </p>\n\n<p><strong>Why doesn't crossing your eyes cause any damage?</strong></p>\n\n<p>Now, that I've gone over the what, I'll go over the why. Many times throughout the day, you will cross your eyes on purpose, but won't actually think of it as crossing your eyes. Crossing your eyes is the natural reaction to looking at something very close to your face. We need to angle our eyes so we can see objects clearly at a close range. This is essentially the same exact movement you would make when crossing your eyes. Our eyes are designed to be able to move up, down, left, and right, and, while it may not seem like the most natural eye movement, crossing your eyes voluntarily is completely normal.</p>\n\n<p>There is a potential for temporary disorientation, pain, or possible blurring if you cross your eyes for too long, but it would only last a short amount of time. This is because you would be putting more strain on the muscles in your eyes, in this case it would mostly be your <a href=\"http://www.healthline.com/human-body-maps/medial-rectus-muscle\" rel=\"noreferrer\">medial rectus muscles</a>. All you need to recover from this is to just rest your eye muscles, just as you would after a workout.</p>\n\n<hr>\n\n<p><sup><a href=\"https://books.google.com/books?id=7aRg3fVCpEkC&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false\" rel=\"noreferrer\">Don't Cross Your Eyes...They'll Get Stuck That Way!: And 75 Other Health Myths Debunked</a></sup></p>\n\n<p><sup><a href=\"http://mayoclinichealthsystem.org/locations/la-crosse/medical-services/ophthalmology/myths-and-facts\" rel=\"noreferrer\">Ophthalmology: Eye Myths and Facts</a></sup></p>\n", "score": 5 } ]
3,696
Can crossing my eyes damage them?
[ "eye", "lifestyle", "vision" ]
<p>I am able to cross my eyes when I want. Can doing this somehow damage my vision by giving me <a href="https://www.nlm.nih.gov/medlineplus/ency/article/001004.htm" rel="nofollow">strabismus</a>?</p>
9
https://medicalsciences.stackexchange.com/questions/3817/how-long-should-you-wait-after-lunch-if-you-want-to-take-a-bath-and-why
[ { "answer_id": 14397, "body": "<blockquote>\n<ul>\n<li>Is it true that one shouldn't take a bath after lunch?</li>\n</ul>\n</blockquote>\n<p>No.\nThat's a long hold myth, nothing more.</p>\n<p>Although it might have all the pedagogical value of scare stories in general:</p>\n<blockquote>\n<p><a href=\"http://www.bbc.com/future/story/20130401-can-you-swim-just-after-eating\" rel=\"nofollow noreferrer\">So telling kids they might drown because they’ve just eaten is one way of getting them to listen to you. But from the evidence, it doesn’t appear to be backed up by science.</a></p>\n</blockquote>\n<p>Bathing is less demanding than swimming? Most of these beliefs centre around swimming which might be a cause of discomfort, even minor cramps:</p>\n<blockquote>\n<p>Eating-Exercise Connection:\n<a href=\"https://www.dukehealth.org/blog/myth-or-fact-should-you-wait-swim-after-eating\" rel=\"nofollow noreferrer\">Even though this particular example is a myth, the relationship between eating and exercise is important. Knowing when and what to eat can make a difference in how many calories you burn and how effective your workout is.</a></p>\n</blockquote>\n<p>If you take to mean lunch in the South of Europe, where drinking alcohol with meals is customary, than the picture might change a little bit:</p>\n<blockquote>\n<p><a href=\"http://www.nytimes.com/2005/06/28/health/the-claim-never-swim-after-eating.html\" rel=\"nofollow noreferrer\">But meals that include a drink or two are another story. In 1989, for example, a study in the journal Pediatrics looked at almost 100 adolescents who drowned in Washington and found that 25 percent had been intoxicated. One year later, a study of hundreds of drowning deaths among adults in California found that 41 percent were alcohol related.</a></p>\n<p><strong>The Bottom Line</strong> Swimming after a meal will not increase the risk of drowning, unless alcohol is involved</p>\n</blockquote>\n<p>But it seems to persist since even health organisations like the Red Cross <em>once</em> did give out advice along those lines. <a href=\"https://www.redcross.org/images/MEDIA_CustomProductCatalog/m3240085_SwimmingWaterSafety.pdf\" rel=\"nofollow noreferrer\">Not any longer</a>:</p>\n<blockquote>\n<p><a href=\"https://www.medicinenet.com/summer_debunking_summer_health_myths/views.htm\" rel=\"nofollow noreferrer\">False: Wait a half hour after eating before you can safely go swimming\nThis one seemed almost universally accepted when I was a child and is still believed today. The myth involves the possibility of suffering severe muscle cramping and drowning from swimming on a full stomach. While it's true that the digestive process does divert the circulation of the blood toward the gut and to a certain extent, away from the muscles, the fact is that an episode of drowning caused by swimming on a full stomach has never been documented. Neither the American Academy of Pediatrics nor the American Red Cross makes any specific recommendations about waiting any amount of time after eating before taking a swim. There's a theoretical possibility that one could develop a cramp while swimming with a full stomach, but a person swimming in a pool or controlled swimming area could easily exit the water if this happens. As with any exercise after eating, swimming right after a big meal might be uncomfortable, but it won't cause you to drown.</a></p>\n</blockquote>\n<p>For possible origins of this myth:</p>\n<blockquote>\n<p><a href=\"https://health.howstuffworks.com/mental-health/human-nature/health-myths/swimming-after-eating.htm/printable\" rel=\"nofollow noreferrer\">No one is quite sure when or why parents began telling their children to wait an hour after eating before setting so much as a little toe in the pool or lake. Two popular theories abound, one biological and the other social.</a></p>\n</blockquote>\n<p>And scientists have objected these theories for quite a while now:</p>\n<blockquote>\n<p><a href=\"https://www.snopes.com/oldwives/hourwait.asp\" rel=\"nofollow noreferrer\">In 1961 exercise physiologist Arthur Steinhaus took a position against this belief in the Journal of Health, Physical Education, and Recreation. He labeled the very idea of stomach cramps “questionable.”</a></p>\n</blockquote>\n", "score": 5 } ]
3,817
CC BY-SA 3.0
How long should you wait after lunch if you want to take a bath, and why?
[ "digestion", "time-of-day", "bath", "meal", "water-temperature" ]
<p>Is it true that one shouldn't take a bath after lunch? If so, does it depend on </p> <ul> <li>how heavy the lunch is? </li> <li>whether one is taking a bath or a shower or bathing in a river? </li> <li>how warm or cold the water is? </li> </ul> <p>Often, I tend to be in a situation where I go for lunch first and then for bath. So I was wondering, whether it interferes either with digestion or with anything else. </p> <p>Two contexts for this question (in response to the suggestion in the comments) : </p> <p>Note : I am not looking for answers for the contexts below, but rather for the questions above. </p> <ol> <li><p>I have heard a vague saying somewhere, that after a lunch, maximum blood flow is directed to the intestines and a bath might interfere with the digestion. (Purely anecodatal hearsay). I noticed that we burp a bit during the bath, if you have a bath after lunch. </p></li> <li><p>We were once touring a hilly area. We had food at a roadside joint and soon after jumped into the cold river (yes, very cold). After we were back at our room, two of my friends had a severe stomach upset, and two others quite uncomfortable, although I was fine. </p></li> </ol>
9
https://medicalsciences.stackexchange.com/questions/3838/can-gerd-be-caused-by-too-little-stomach-acid
[ { "answer_id": 3899, "body": "<p>Increased levels of stomach acid aren't actually listed as causes for GERD anywhere I could find. It is listed as a cause for ulcers, but not GERD:</p>\n<blockquote>\n<p>Increased levels of gastrin can cause increased release of acid and may lead to ulcers (Zollinger-Ellison syndrome)</p>\n</blockquote>\n<p>[<a href=\"https://www.nlm.nih.gov/medlineplus/ency/article/003883.htm\" rel=\"nofollow noreferrer\">Stomach acid test</a> - What Abnormal Results Mean]</p>\n<p>Gastroesophageal reflux disease occurs when stomach acid enters the esophagus. Normally, the lower esophageal sphincter closes off the stomach. If it doesn't close completely, stomach acid moves upwards and hurts the esophagus that doesn't have the same lining as the stomach to protect it from the acid.</p>\n<blockquote>\n<p>GERD is caused by frequent acid reflux — the backup of stomach acid or bile into the esophagus.</p>\n<p>When you swallow, the lower esophageal sphincter — a circular band of muscle around the bottom part of your esophagus — relaxes to allow food and liquid to flow down into your stomach. Then it closes again.</p>\n<p>However, if this valve relaxes abnormally or weakens, stomach acid can flow back up into your esophagus, causing frequent heartburn.</p>\n</blockquote>\n<p>[<a href=\"http://www.mayoclinic.org/diseases-conditions/gerd/basics/causes/con-20025201\" rel=\"nofollow noreferrer\">Mayo Clinic - GERD</a>]</p>\n<blockquote>\n<p>GER and GERD happen when your lower esophageal sphincter becomes weak or relaxes when it shouldn’t, causing stomach contents to rise up into the esophagus. The lower esophageal sphincter becomes weak or relaxes</p>\n</blockquote>\n<p>[<a href=\"http://www.niddk.nih.gov/health-information/health-topics/digestive-diseases/ger-and-gerd-in-adults/Pages/symptoms-causes.aspx\" rel=\"nofollow noreferrer\">The National Institute of Diabetes and Digestive and Kidney Diseases</a>]</p>\n<p>A good overview of this with citations was also just added as an answer to another question here: <a href=\"https://health.stackexchange.com/questions/1341/what-is-the-mechanism-of-heartburn\">What is the mechanism of heartburn</a></p>\n<p>The possible causes of the esophageal sphincter becoming weak are listed as</p>\n<ul>\n<li>pressure on the abdomen</li>\n<li>certain medications</li>\n<li>smoking</li>\n<li>a condition called a hiatal hernia</li>\n</ul>\n<p>A hiatal hernia is an anatomical cause.</p>\n<blockquote>\n<p>A hiatal hernia occurs when part of your stomach pushes upward through your diaphragm</p>\n</blockquote>\n<p>[<a href=\"http://www.mayoclinic.org/diseases-conditions/hiatal-hernia/basics/definition/con-20030640\" rel=\"nofollow noreferrer\">Mayo Clinic - Hiatal Hernia</a>]</p>\n<p>The exact causes of hiatal hernias is unknown, one suspected cause is pressure put on the stomach. In some people, it just seems to appear when they get older.</p>\n<p>If GERD isn't caused by too much stomach acid, then why are acid reducing drugs prescribed as treatment? <em>Because the less acid there is - and therefore the less acidic the stomach contents are - the less damage it can do to the esophagus.</em> Proton pump inhibitors even allow the damage to the esophagus to heal. Other options for treating GERD are <a href=\"http://www.mayoclinic.org/diseases-conditions/gerd/basics/treatment/con-20025201\" rel=\"nofollow noreferrer\">medication and surgery to strengthen the esophageal sphincter</a>.</p>\n<p>In light of the evidence for weak esophageal sphincters being the cause for GERD, I'd consider low stomach acid being a cause an unlikely hypothesis.</p>\n<p>+++</p>\n<p>In regards to your edit, here is my main disagreement / concern</p>\n<blockquote>\n<p>This reasoning behind this is that undigested food is putrefying and rotting, expelling gas within the stomach, then increasing pressure on the LES.</p>\n</blockquote>\n<p>Food doesn't rot in the stomach. Food stays in the stomach <a href=\"http://www.vivo.colostate.edu/hbooks/pathphys/digestion/basics/transit.html\" rel=\"nofollow noreferrer\">for less than six hours</a>, which we know because we can track it. It spends most of its time in the colon. Food doesn't begin rotting within six hours, especially not while in the stomach, where, even in people with low stomach acidity, the acid kills most bacteria that could make the food rot.</p>\n<p>What really makes me doubt this, though, is that there are people who don't produce, or produce very low levels of stomach acid. That condition is called <em><a href=\"http://emedicine.medscape.com/article/170066-overview#a4\" rel=\"nofollow noreferrer\">achlorhydria</a></em> and is defined as</p>\n<blockquote>\n<p>an intragastric pH greater than 5.09 in men and greater than 6.81 in women.</p>\n</blockquote>\n<p>Normal values are between 1 and 3. Since pH is a logarithmic scale, this is a big difference.</p>\n<p>The symptoms seen even in these patients do not <a href=\"http://www.mdguidelines.com/achlorhydria-and-hypochlorhydria\" rel=\"nofollow noreferrer\">generally include chronic acid reflux</a>.</p>\n<p>It is very hard to even try to refute those sources, as they regularly state such things as</p>\n<blockquote>\n<p>It is estimated that 80% of people with food allergies suffer from some degree of low acid production in the stomach</p>\n</blockquote>\n<p>without any citation. Or that rheumatoid arthritis is caused by poor digestion. Or that food used to include &quot;digestive enzymes&quot;, but doesn't anymore. These are signs of pseudoscience and does not make me confident that anything else on that site is scientifically sound.</p>\n<blockquote>\n<p>Then, the rotting food causes inflammation in the stomach which results in the stomach producing less acid,</p>\n</blockquote>\n<p>First of all, that source is about gastritis, not acid reflux. It says nothing about rotting food. It's about the complete opposite - how gastritis (and ulcers) needs to be treated by lowering the stomach pH so the stomach lining can heal. After that, proton pump inhibitors are discontinued and the stomach acid returns to normal levels. The inflammation of the stomach in gastritis (usually caused by taking NSAIDs) does not somehow cause a lower stomach acidity, which seems to be what you are implying.</p>\n<p>There is a longer refutation of some claims here: <a href=\"http://digestivehealthinstitute.org/2014/07/10/h-pylori-low-stomach-acid-gerd/\" rel=\"nofollow noreferrer\">Is GERD caused by H. pylori &amp; Low Stomach Acid?</a>. That article includes several links to studies that show patients with GERD not having significantly lower stomach acidity than patients without GERD and that artifically lowering stomach acidity triggered more severe GERD symptoms. I am not sure how unbiased it is, but I highly recommend looking at it and <strong>its sources</strong>.</p>\n<p>Another interesting paper is <a href=\"http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2036.1996.d01-506.x/abstract\" rel=\"nofollow noreferrer\">Altered bowel function and duodenal bacterial overgrowth in patients treated with omeprazole</a>, which concluded that in people treated with PPIs (and thus lowered stomach acidity), food stays in the digestive tract for a shorter, not longer, duration.</p>\n<p>A final recommendation: If you, yourself, are concerned about this, get your stomach pH tested. That's something that can be done.</p>\n<blockquote>\n<p>In my opinion, we could have millions of sufferers in our country, and for that reason I want to find out the truth.</p>\n</blockquote>\n<p>Well, evaluating new hypotheses is outside the scope of this site. I have given you the state of research as I understand it and have tried looking at the references you presented, but found them severely lacking. But of course, I don't know what &quot;the truth&quot; is.</p>\n", "score": 7 } ]
3,838
CC BY-SA 4.0
Can GERD be caused by too little stomach acid?
[ "gastroenterology", "stomach", "gerd-acid-reflux", "lower-esoph-sphincter-les", "integrative-medicine" ]
<p>Ever since the book, <a href="http://www.goodreads.com/book/show/721913.Why_Stomach_Acid_Is_Good_for_You" rel="nofollow">Why Stomach Acid is Good For You</a>, I've wondered if it is true that GERD can be caused by too little, not too much, stomach acid. Is it possible that too little stomach acid can cause GERD? If so, by what mechanism would this occur?</p> <p><strong>EDIT - After reading the answer below, I’d like to add a little more information.</strong></p> <p>I don’t disagree with the fact that GERD is caused by a malfunctioning lower esophageal sphincter (LES), and I don’t disagree with known causes that would contribute to a malfunctioning LES, but what seems very likely to me is that low stomach acid is an additional cause of a malfunctioning LES. This reasoning behind this is that undigested food is putrefying and rotting, expelling gas within the stomach, then increasing pressure on the LES. It could even be possible that low stomach acid is the cause in a large majority of the cases of GERD.</p> <p>There is an entire integrative medicine field, aka holistic health, that has identified in many cases GERD is actually caused by too little stomach acid (<a href="http://drsircus.com/medicine/cancer-gerd/" rel="nofollow">1</a>, <a href="http://chriskresser.com/what-everybody-ought-to-know-but-doesnt-about-heartburn-gerd/" rel="nofollow">2</a>, <a href="http://drmyhill.co.uk/wiki/Hypochlorhydria_-_lack_of_stomach_acid_-_can_cause_lots_of_problems" rel="nofollow">3</a>). And while I am usually not one to ever listen to this field of medicine, they make some really astute observations.</p> <ul> <li><a href="http://www.webmd.com/cancer/features/esophageal-cancer-rise" rel="nofollow">Esophageal cancer is on the sharp rise</a>, coincidentally in an era with the most robust acid reducing medication available.</li> <li><a href="https://books.google.com/books?id=FK6g2eRpbvUC&amp;pg=PA17&amp;lpg=PA17&amp;dq=stomach%20acid%20production%20decreases%20with%20age&amp;source=bl&amp;ots=wv3LFMAa-0&amp;sig=hqmuc7H0rdGY4DAiCalZ7lo64lY&amp;hl=en&amp;sa=X&amp;ved=0ahUKEwj2uaCk_L3JAhVH7GMKHRj3B084ChDoAQgzMAQ#v=onepage&amp;q=stomach%20acid%20production%20decreases%20with%20age&amp;f=false" rel="nofollow">Stomach acid production declines with age</a>.</li> <li><a href="http://jonbarron.org/article/stomach-acid" rel="nofollow">Food nowadays lacks enzymes, which causes digestive organs to overwork, causing the acid producing mechanism of the stomach to fatigue</a>.</li> <li><a href="http://www.westonaprice.org/modern-diseases/against-the-grain/" rel="nofollow">GMO Wheat 3.0 has gluten proteins which are undigestible to many people</a>.</li> </ul> <p>I realize this isn’t what the mainstream doctors believe, but the mainstream is being influenced by a 15 billion dollar industry. The PPI section in the store is huge. I’ve been to multiple gastro docs, and it’s like assembly line Prilosec prescribing. Two people who know our family, that have both been diagnosed with esophageal cancer, just happen to be taking Prilosec / Nexium for many years prior. Another friend had to have is colon cut out because of a bacterial infection, which could have been caused by the elimination of the body’s first line of bacterial defense (stomach acid).</p> <p>All evidence pointing to low stomach acid seems legitimate, so why not give it proper attention. So here I’d like to diagram what I believe to be the problem: the step-ladder catch-22 inflammation and putrefication snowball effect. Remember, all of this is on the basis that when it comes to low stomach acid, GERD is being caused by the rotting / putrefication of food in the stomach (due to the pyloric sphincter remaining shut) and the resulting gasses which bubble up past the 2-way LES causing GERD. Then, the rotting food causes <a href="http://www.niddk.nih.gov/health-information/health-topics/digestive-diseases/gastritis/Pages/facts.aspx" rel="nofollow">inflammation in the stomach which results in the stomach producing less acid</a>, and the problem starts to compound. It basically goes like this:</p> <blockquote> <p>Eat Meal -> Low Acid -> Undigested Food -> Pyloric Sphincter Stays Shut -> Putrefying &amp; Rotting (GERD) -> Gastric Inflammation -> Next Meal -> Lower Acid -> Undigested Food -> Pyloric Sphincter Stays Shut -> Putrefying &amp; Rotting (GERD) -> More Gastric Inflammation -> Next Meal -> Lower Acid -> Undigested Food -> Pyloric Sphincter Stays Shut -> Putrefying &amp; Rotting (GERD) -> More Gastric Inflammation -> And So On…</p> </blockquote> <p>When you go down this step-ladder road for a few months, the avenue out of it is daunting, if not impossible. In my opinion, we could have millions of sufferers in our country, and for that reason I want to find out the truth.</p>
9
https://medicalsciences.stackexchange.com/questions/3972/is-there-any-treatment-for-autism
[ { "answer_id": 3981, "body": "<p>This is really interesting, and really difficult. </p>\n\n<p>First, let's get <strong>Miracle Mineral Supplement</strong> out of the way. There is a lengthy article on this up on the blog \"Science-based Medicine\" called <a href=\"https://www.sciencebasedmedicine.org/bleaching-away-what-ails-you/\" rel=\"nofollow noreferrer\">Bleaching away what ails you</a>. That article is quite good, but uses strong language, so it isn't for everyone. It describes the rhetoric around MMS, especially in regards to how it's used on autistic children. </p>\n\n<p>First of all, what is MMS? It's diluted sodium chlorite, a bleach. And the person who sells it <a href=\"http://miraclemineral.org/the-author/authors-message\" rel=\"nofollow noreferrer\">claims</a> it basically cures anything. </p>\n\n<blockquote>\n <p>Well, it overcomes colds in an hour or so, overcomes flu in less than 12 hours, overcomes pneumonia in less than 12 hours, cures more cancer than any other treatment by hundreds of times, cures hepatitis A, B, and C. It cures appendicitis, rheumatoid arthritis, and a hundred other diseases.</p>\n</blockquote>\n\n<p>That alone should be enough to make anyone skeptical. The flu is a viral infectious disease of the respiratory tract. Rheumatoid arthritis is an incurable autoimmune disease. Appendicitis is an inflammation of the bowel. These are wildly different things, and that's not counting the \"hundred other diseases\". The two probably most potent medicines we have, antibiotics and steroids, don't even claim to be effective for all of these. </p>\n\n<p>As a bleach, MMS can cause serious complications. The Food and Drug Administration in the United States <a href=\"http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm220756.htm\" rel=\"nofollow noreferrer\">strongly warns people not to use it</a></p>\n\n<blockquote>\n <p>FDA warned consumers not to consume or use Miracle Mineral Solution, an oral liquid solution also known as \"Miracle Mineral Supplement\" or \"MMS.\" The product, when used as directed, produces an industrial bleach that can cause serious harm to health. The product instructs consumers to mix the 28 percent sodium chlorite solution with an acid such as citrus juice. This mixture produces chlorine dioxide, a potent bleach used for stripping textiles and industrial water treatment. High oral doses of this bleach, such as those recommended in the labeling, can cause nausea, vomiting, diarrhea, and symptoms of severe dehydration</p>\n</blockquote>\n\n<p>The government agency \"Health Canada\" <a href=\"http://www.cbc.ca/beta/news/health/health-canada-warning-stop-using-miracle-mineral-solution-immediately-1.2804787\" rel=\"nofollow noreferrer\">has seized MMS from a supplied selling it</a></p>\n\n<p><strong>MMS and autism</strong></p>\n\n<p>Does MMS cure autism? Science doesn't usually say \"we are 100 percent sure this doesn't happen\". But in this case, it's probably pretty close. </p>\n\n<p>All that the belief is based on are anecdotes, there are no scientific studies on this at all. There is also no proposed - MMS is a disinfectant, but autism isn't caused by an infection. </p>\n\n<p>Autism doesn't stay constant. For example, there is a question here on Health.SE about autism and fever - <a href=\"https://health.stackexchange.com/questions/3302/why-do-80-of-children-with-autism-appear-to-improve-when-they-have-a-fever#\">autism symptoms improve when patients have a fever</a>. </p>\n\n<p><strong>Treatment of autism</strong></p>\n\n<p><a href=\"http://www.nimh.nih.gov/health/topics/autism-spectrum-disorders-asd/index.shtml\" rel=\"nofollow noreferrer\">Autism spectrum disorder is a wide field of syndromes</a>. From high-functioning individuals to people who need constant caregiving. There are no cures. </p>\n\n<p><a href=\"http://www.cdc.gov/ncbddd/autism/treatment.html\" rel=\"nofollow noreferrer\">Treatment includes various options.</a></p>\n\n<p><em><a href=\"https://www.nichd.nih.gov/health/topics/autism/conditioninfo/Pages/medication-treatment.aspx\" rel=\"nofollow noreferrer\">Medication</a></em></p>\n\n<blockquote>\n <p>Currently, there is no medication that can cure ASD or all of its symptoms. But in many cases, medication can help treat some of the symptoms associated with ASD, especially certain behaviors.</p>\n</blockquote>\n\n<p>These behavioral issues are, for example, anxiety, repetitive behavior, hyperactivity and loss of focus, seizures (which one third of people with autism have), etc. </p>\n\n<p>There are studies being done on more treatment options, for example on whether <a href=\"https://www.autismspeaks.org/science/science-news/researchers-launch-study-oxytocin-nasal-spray\" rel=\"nofollow noreferrer\">oxytocin could help</a>. </p>\n\n<p><em>Behavioral Therapy</em></p>\n\n<p>Behavioral therapy is a big focus in the treatment of autism. Much of this is focused on children. I'm just going to link to and summarize a few of the resources on this. </p>\n\n<blockquote>\n <p>A notable treatment approach for people with an ASD is called applied behavior analysis (ABA). ABA has become widely accepted among health care professionals and used in many schools and treatment clinics. ABA encourages positive behaviors and discourages negative behaviors in order to improve a variety of skills. The child’s progress is tracked and measured.</p>\n</blockquote>\n\n<p><a href=\"http://www.cdc.gov/ncbddd/autism/treatment.html\" rel=\"nofollow noreferrer\">CDC - Treatment of ASD</a></p>\n\n<blockquote>\n <p>Scientific studies have demonstrated that early intensive behavioral intervention improves learning, communication and social skills in young children with autism. While the outcomes of early intervention vary, all children benefit. Researchers have developed a number of effective early intervention models. </p>\n</blockquote>\n\n<p><a href=\"https://www.autismspeaks.org/what-autism/treatment\" rel=\"nofollow noreferrer\">Autism Speaks - How is Autism Treated</a></p>\n\n<p><em>Other Treatments</em></p>\n\n<p>Two other often mentioned treatments for ASD are dietary changes, especially a gluten free diet, and chelation. </p>\n\n<p>A Cochrane review titled <a href=\"http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD010766.pub2/abstract\" rel=\"nofollow noreferrer\">Chelation for autism spectre disorder</a> summarizes:</p>\n\n<blockquote>\n <p>no clinical trial evidence was found to suggest that pharmaceutical chelation is an effective intervention for ASD. Given prior reports of serious adverse events, such as hypocalcaemia, renal impairment and reported death, the risks of using chelation for ASD currently outweigh proven benefits</p>\n</blockquote>\n\n<p>As such, chelation shouldn't be used. </p>\n\n<p>Another, titled <a href=\"http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD003498.pub3/abstract\" rel=\"nofollow noreferrer\">Gluten- and casein-free diets for autistic spectrum disorder</a> summarizes the research on the most popular dietary restriction:</p>\n\n<blockquote>\n <p>Research has shown of high rates of use of complementary and alternative therapies (CAM) for children with autism including gluten and/or casein exclusion diets. Current evidence for efficacy of these diets is poor. Large scale, good quality randomised controlled trials are needed.</p>\n</blockquote>\n\n<p><strong>Cure</strong></p>\n\n<p>I wrote before that autism can't be cured. However, </p>\n\n<blockquote>\n <p>Growing evidence suggests that a small minority of persons with autism progress to the point where they no longer meet the criteria for a diagnosis of autism spectrum disorder (ASD). </p>\n</blockquote>\n\n<p>Since the diagnosis of autism isn't based on the presence of a virus or something, therapy and treatment can actually mean a person progresses to the point of no longer meeting all diagnostic criteria. </p>\n", "score": 4 }, { "answer_id": 4661, "body": "<p>The closest thing I'm aware of as a cure for autism is Early Intensive Behavioural Therapy. The idea behind it is to train the autistic child in basic social behaviours within the timeframe that they would normally be acquiring them, from 0-5 years. </p>\n\n<p>As far as I'm aware it's ineffective after the age of 5 because the parts of the brain that it's meant to train will have been pruned by the normal synaptic pruning mechanism, making it much harder for the child to develop the social skills as there's no longer a part of the brain that's 'primed' to handle that task.</p>\n\n<p><a href=\"http://www.ncbi.nlm.nih.gov/pubmed/23076956\" rel=\"nofollow\">PubMed article about EIBI</a></p>\n", "score": 1 } ]
3,972
CC BY-SA 3.0
Is there any treatment for autism?
[ "treatment", "autism" ]
<p>Are there any treatments that can help improve the cognitive function of people with autism? </p> <p>I've also heard about <a href="https://en.wikipedia.org/wiki/Miracle_Mineral_Supplement">Miracle Mineral Supplement (MMS)</a> being a cure for autism. Does this claim have any truth to it?</p>
9
https://medicalsciences.stackexchange.com/questions/4023/is-eyebrow-hair-loss-common-in-hyperthyroidism
[ { "answer_id": 10447, "body": "<p>The condition that you're asking about is called in the professional terminology: \"<strong>madarosis</strong>\" (but see the picture that I attached). As many proffessional books states, it's common in hypothyroidism, and they don't say it about hyperthyroidism. Then it make sense that it's not <em>common</em> in hyperthyroidism. But in medicine always can be exceptions. </p>\n\n<p>Regarding to the side effect of carbimazole, according to <a href=\"http://www.ehealthme.com/ds/methimazole/madarosis/\" rel=\"nofollow noreferrer\">this source</a> which rely on FDA report, there is no such side effect of carbimazole, and obviously it is not common as well. </p>\n\n<blockquote>\n <p>\"Could Methimazole cause Madarosis? - from FDA reports</p>\n \n <p>There is no Madarosis reported by people who take Methimazole yet. We\n study 2,148 people who have side effects while taking Methimazole from\n FDA. Find out below who they are, when they have Madarosis and more.</p>\n</blockquote>\n\n<p>Bibiligraphy: </p>\n\n<p>1) Thyroid Disorders with Cutaneous Manifestations (p.129) </p>\n\n<p>2) Illustrated Synopsis of Dermatology &amp; Sexually Transmitted Diseases (p.384)</p>\n\n<p>3) <a href=\"http://www.ehealthme.com/ds/methimazole/madarosis/\" rel=\"nofollow noreferrer\">http://www.ehealthme.com/ds/methimazole/madarosis/</a></p>\n\n<p><a href=\"https://i.stack.imgur.com/krG3G.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/krG3G.png\" alt=\"enter image description here\"></a></p>\n\n<p><a href=\"https://i.stack.imgur.com/576mb.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/576mb.png\" alt=\"enter image description here\"></a></p>\n", "score": 3 } ]
4,023
CC BY-SA 3.0
Is eyebrow hair loss common in hyperthyroidism?
[ "hairloss", "thyroid", "hyperthyroid", "eyebrows" ]
<p>I have seen many articles talking about hair loss in regards to <em>hypothyroidism</em> but very few about <em>hyperthyroidism</em>. People suffer from hair loss in both thyroid diseases, but is it common to lose hair from the eyebrows while on <strong>carbimazole</strong> for treatment of <em>hyperthyroidism</em>?</p> <p>I mean both, hair loss because of the carbimazole or because of the hyperthyroid disorder. </p>
9
https://medicalsciences.stackexchange.com/questions/4040/are-there-any-health-hazards-related-to-raw-veganism
[ { "answer_id": 15765, "body": "<p>I think the main hazards associated with raw veganism would be more around food hygiene. Without a kill-step (i.e. cooking to over 75 degrees Celsius) and hygienic food preparation practices there is the potential to be exposed to harmful bacteria, in particular salmonella is associated with bean sprouts and melons.\nWash your veggies, and if you're concerned about nutrition, it's best to talk to your local GP or a nutritionist/dietician. </p>\n\n<p><a href=\"http://foodsafety.asn.au/fruit-and-vegetables/\" rel=\"nofollow noreferrer\">http://foodsafety.asn.au/fruit-and-vegetables/</a> </p>\n", "score": 3 } ]
4,040
CC BY-SA 3.0
Are there any health hazards related to raw veganism?
[ "nutrition", "vegetarianism", "proteins" ]
<p>I was talking to a friend yesterday about <a href="https://en.wikipedia.org/wiki/Raw_veganism" rel="noreferrer">raw veganism</a> and he expressed his concerns about it because he thinks that raw vegans can't metabolize proteins adequately due to the low temperature they use to cook their food.</p> <p>I was wondering if there are any health hazards related to raw veganism besides lack of B-12 protein (which as far as I know is something common to all kinds of veganism) and similar stuff.</p>
9
https://medicalsciences.stackexchange.com/questions/4041/what-are-side-effects-frequencies-based-on
[ { "answer_id": 4177, "body": "<p>Side effects frequency narrative words are defined by the council of International Organizations of Medical Sciences. See slide 10 of this <a href=\"http://www.who.int/medicines/areas/quality_safety/safety_efficacy/trainingcourses/definitions.pdf\">presentation on the subject</a>. As shown, \"Very common\" means equal to or greater than 10% [of the patients tested for that drug]. \"Common\" or \"frequent\" means more than 1% but less than 10%. \"Uncommon\" or \"infrequent\" means between 1 per 1,000 and 1%. Rare means equal to or more than 1 per 10,000 but less than 1 per 1,000. Very rare means less than 1 per 10,000. </p>\n\n<p>In turn, for any specific drugs the above metrics are derived, not by doctors, but by specialized clinical trials statisticians conducting clinical trials of such drugs. Clinical trials are conducted by separating patients into at least two groups. One control group just takes a placebo. The test group takes the drug. This type of study is sometimes called randomized double blind placebo control study. This process is further described in this <a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3505292/\">paper</a>. You conduct the clinical trial for a certain period of time. And, then you observe the frequencies of side effects using the semantic as described above. Granted, the statisticians deal with the actual precise numbers and are not satisfied by using narrative categories instead of calculations. </p>\n\n<p>Next, the statisticians will compare the frequency of side effects between the Control group and the Test group. And, they pay much attention where the Test group's side effects are much larger than for the Control group. And, they measure whether that difference is real and not due to just randomness. The latter (probability that occurence is just random) is captured in a probability called a p-value. If that p-value is less than 0.05, the side effect is deemed to be statistically significant (and greater than for placebo).</p>\n\n<p>In the US, the mentioned clinical trials are submitted for assessment and drug approval or denial to the Federal Drug Administration (FDA). In Germany, such clinical trials are submitted to Bundesinstitut für Arzneimittel und Medizinprodukte <a href=\"http://www.bfarm.de/EN/Home/home_node.html\">BfArM</a>.</p>\n\n<p>If you are interested on the subject, the BfArM website has most probably some very interesting information.</p>\n", "score": 6 } ]
4,041
CC BY-SA 3.0
What are side effects frequencies based on?
[ "medications", "side-effects", "research", "practice-of-medicine" ]
<p>I am one of these patients who reads everything that comes with their pills. Including, of course, the sometimes really long side effects list. Where I am, and from what I read online this is common, these side effects are sorted into several frequency categories (common/rare/very rare/sporadic, something like that). </p> <p>Yesterday, after years, I realized I had no idea where those frequencies come from. Do they come from scientific studies? From people participating in really large-scale trials? </p> <p>Or from doctors reporting back on what their patients report? From patients reporting it? But then, how are the frequencies determined? "Common", for example means something around 10 percent where I am, so you don't just need to know how many people report that side effect, you need to know how many people took the medication (and did so as instructed, and didn't take anything that interfered with it, etc.). </p> <p>So, <strong>where do these frequencies and these lists of side effects come from?</strong> </p> <p>I'm in Germany, but I am open to an answer as to how this works in any country. </p>
9
https://medicalsciences.stackexchange.com/questions/4100/hashimoto-thyroiditis-leading-to-severe-psychological-problems-and-behavior-chan
[ { "answer_id": 5107, "body": "<p>A literature search (as well as my education) reveal the following:</p>\n\n<p><a href=\"http://europepmc.org/abstract/med/16444160\" rel=\"noreferrer\">Hashimoto thyroiditis</a> causes inflammation of the thyroid hormone producing cells in the thyroid gland. This can lead to hypothyroidism as the <a href=\"http://jama.jamanetwork.com/article.aspx?articleid=375004\" rel=\"noreferrer\">associated symptoms</a>. In the initial phase though, the inflammation may cause a sudden \"leaching\" out or release of the already formed thyroid hormone causing a hyperthyroid state known as Hashimoto thyroxicosis which can produce hyperthyroidism <a href=\"http://onlinelibrary.wiley.com/doi/10.1111/j.1532-5415.1996.tb05637.x/abstract;jsessionid=891E49A6D55B583194EDA6E17543D4B0.f02t04?systemMessage=Wiley%20Online%20Library%20will%20be%20unavailable%20for%20up%20to%203%20hours%20on%20Saturday%2019th%20March%202016%20from%20%2011%3A00-14%3A00%20GMT%20%2F%2007%3A00-10%3A00%20EDT%20%2F%2019%3A00-22%3A00%20SGT%20for%20essential%20maintenance.%20%20Apologies%20for%20the%20inconvenience.&amp;userIsAuthenticated=false&amp;deniedAccessCustomisedMessage=\" rel=\"noreferrer\">related symptoms</a>.</p>\n\n<p>Please see sources above but speaking from my knowledge in addition to the above: Essentially Hashimoto thyroiditis can cause an initial hyperthyroid state. Hyperthyroidism can cause nervousness, tremor, and other neuropsychiatric symptoms. If a patient then later develops clinical hypothyroidism, they can also suffer the neuropsychiatric consequences of hypothroidism which include depression, though can be very severe including coma.</p>\n\n<p>Thyroid hormone acts on many tissues and can essentially affect any organ system. The symptoms therefore can be very broad and nonspecific. The symptoms may also be severe. The psychiatric symptoms are well known. <strong>Therefore, the answer to your question is, yes.</strong></p>\n", "score": 5 } ]
4,100
CC BY-SA 3.0
Hashimoto thyroiditis leading to severe psychological problems and behavior changes?
[ "mental-health", "endocrinology", "autoimmune-disease", "hypothyroid", "hashimoto-thyroiditis" ]
<p>Can Hashimoto thyroiditis lead to psychological problems and severe behavioral changes?</p> <p>Do existing psychological problems (anxiety, depression, etc.) 'compound' when layered with Hashimoto thyroiditis? </p>
9
https://medicalsciences.stackexchange.com/questions/4103/what-is-the-distribution-of-corrected-visual-acuity
[ { "answer_id": 10600, "body": "<p>Most people will tolerate a visual acuity of up to 20/40 (being able to read something at 20 feet that a normal person with \"perfect\" vision can read at 40 feet) before seeing a physician. According to this article (<a href=\"https://www.ncbi.nlm.nih.gov/pubmed/16325714\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pubmed/16325714</a>), patients over the age of 65 are more likely to tolerate this level of vision before seeking proper correction, similar to your statement of their vision being \"good enough\". </p>\n\n<p>Other articles that touch on this topic include the following:</p>\n\n<ul>\n<li><a href=\"https://www.ncbi.nlm.nih.gov/pubmed/18451738\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pubmed/18451738</a></li>\n<li><a href=\"https://www.ncbi.nlm.nih.gov/pubmed/18161606\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pubmed/18161606</a></li>\n</ul>\n", "score": 3 } ]
4,103
CC BY-SA 3.0
What is the distribution of corrected visual acuity?
[ "eye", "statistics", "optometry", "visual-acuity" ]
<p>While talking with friends about retina displays, resolution of TVs in relation to viewing distance, and so on, I pointed out that not everyone goes periodically to the eye doctor, unless the difficulty in seeing is evident. Not everyone therefore needs retina displays.</p> <p>I wonder what is the actual distribution, if known, of the actually corrected visual acuity in the population.</p> <p>I'm not referring to the achievable acuity after perfect correction, I'm referring to the distribution of what people tolerate before going to the doctor and have the glasses updated. For example, I know that many young or mature people with about 0.9975 (decimal scale, also called -0.25 dioptries) do not wear glasses at all because not worth the effort. Older people typically care even less about proper correction, because their "good enough" is broader.</p> <p>Are there studies that measured this parameter?</p>
9
https://medicalsciences.stackexchange.com/questions/4249/is-there-any-way-to-overcome-attention-deficit-hyperactivity-disorder-without-us
[ { "answer_id": 4252, "body": "<p>In regards to your psychologist, remember that it often takes time before you find one that suits you. Perhaps this one simply isn't suitable?</p>\n\n<p>Cognitive Behavior Therapy (CBT) is an effective non-drug treatment for ADHD. Ask your psychologist about it. </p>\n\n<p>ADHD is postulated to relate to a \"deficiency\" of two chemicals within a particular region of the brain called the prefrontal cortex. Stimulant medications such as Ritalin boost the levels of these chemicals to within a \"normal range\". This is why medication is so effective. Perhaps you would consider medication?</p>\n\n<p>I hate to sound harsh: ADHD is a neurodevelopment disorder. As such, ADHD cannot be \"fixed\", only managed.</p>\n\n<p><strong>References</strong></p>\n\n<ol>\n<li><a href=\"http://www.ncbi.nlm.nih.gov/pubmed/16961428\" rel=\"nofollow\">http://www.ncbi.nlm.nih.gov/pubmed/16961428</a>, Mechanism of action of agents used in attention-deficit/hyperactivity disorder.</li>\n</ol>\n", "score": 4 }, { "answer_id": 4255, "body": "<p>As aduckinthewinter mentioned, ADD/ADHD is not something that can be fixed - just managed. I wouldn't worry at all about trying to \"fix\" your ADD/ADHD, just understand it and work with it.</p>\n\n<p>Some <a href=\"http://www.additudemag.com/adhd/article/612.html\" rel=\"nofollow\">experience hyperfocus</a> if you do, learn to tap into it.</p>\n\n<p>Also make sure that you're getting proper sleep and nutrition. You might try an <a href=\"http://www.additudemag.com/adhd/article/859-4.html\" rel=\"nofollow\">elimination diet</a> to see if you have foods that trigger your inability to focus (you know, like sugar and caffeine).</p>\n\n<p>Pay attention to your body - is there a time during the day that you have better focus? Morning? Night? Midday? Right after a nap? Does music help you focus? Distract you? Software development is actually a creative discipline - and while you do need to be able to focus when you're laying down code, there are a lot of times when you <em>need</em> creativity - even more so in the web sphere.</p>\n\n<p>My personal philosophy is that our society (especially in America) is entirely too bent on making everyone \"average\". We are intolerant of behaviors and attitudes that stand out - unless of course they're at the head of a large organization or are really popular/entertaining. I think that causes a lot of problems with the mental health of a lot of people - in your case it seems like you feel broke and need fixing. In your words:</p>\n\n<blockquote>\n <p>I want to get rid of it totally</p>\n</blockquote>\n\n<p>Why not embrace who you are? Learn what your strengths are and how to use them to your advantage. Learn what your weaknesses are and how trick them into working for you. Like maybe spending a ton of time answering questions on the StackExchange network ;)</p>\n", "score": 2 } ]
4,249
CC BY-SA 3.0
Is there any way to overcome Attention Deficit Hyperactivity Disorder without using medicine?
[ "mental-health", "treatment", "treatment-options", "adhd" ]
<p>I have attention deficit hyperactivity disorder and want to be a web programmer. It's really annoying when you have an error and can't see where it is or can't focus. </p> <p>I tried seeing a psychologist, but it didn't help that much.</p> <p>What I want:</p> <ul> <li><p>I want to overcome it myself </p></li> <li><p>I want to get rid of it totally</p></li> </ul> <p>I am aware that it will take time without professional help, but I don't know how to. </p>
9
https://medicalsciences.stackexchange.com/questions/4251/does-lifting-weights-inhibit-growth-for-teens-and-kids
[ { "answer_id": 4256, "body": "<p>TL; DR: No, they won't impact growth if practiced within reason, and there is no damage to growth plates from injury. </p>\n\n<p>The medical community and the public in general seems to regard strength training as a general voodoo practice that will \"hurt you\". <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/11019731\" rel=\"nofollow noreferrer\">Fortunately, this has been getting debunked soundly for over a decade now</a>.</p>\n\n<blockquote>\n <p>Despite earlier concerns regarding the safety and efficacy of youth\n strength training, current public health objectives now aim to\n increase the number of boys and girls age 6 and older who regularly\n participate in physical activities that enhance and maintain muscular\n fitness.</p>\n</blockquote>\n\n<p><a href=\"http://www.aap.org/en-us/about-the-aap/aap-press-room/Pages/Are-Weights-Safe-for-Kids.aspx\" rel=\"nofollow noreferrer\">The American Academy of Pediatrics recommends strength training for children 8 and up</a>. </p>\n\n<p>Children will tend to play sports much earlier than they can strength train. Those sports and basic calisthenics teach motor control, discipline, and physical prowess. This will provide a great base if you move into supplemental strength training as they become older and can pay attention to training and form elements. In any case, as long as the exercise is age appropriate (Such as don't have your 10 year old squatting 250) and supervised, there shouldn't be an impact.</p>\n\n<p>From there, you have kids who are:</p>\n\n<ul>\n<li>Athletic.</li>\n<li>Used to spending focused time on physical training.</li>\n<li>Used to moving their bodies.</li>\n<li>Used to drills/skills: activities that are not sports themselves, but necessary for helping sports.</li>\n</ul>\n\n<p>Also consider the following two study excerpts:</p>\n\n<blockquote>\n <p>Experimental training protocols with weights and resistance machines and with supervision and low instructor/participant ratios are relatively safe and do not negatively impact growth and maturation of pre- and early pubertal youth.</p>\n</blockquote>\n\n<p><a href=\"http://www.ncbi.nlm.nih.gov/m/pubmed/17119361\" rel=\"nofollow noreferrer\">http://www.ncbi.nlm.nih.gov/m/pubmed/17119361</a></p>\n\n<blockquote>\n <p>Numerous studies have demonstrated that with appropriate supervision and precautions, resistance training can be safe and effective for children and adolescents. </p>\n</blockquote>\n\n<p>and </p>\n\n<blockquote>\n <p>[Resistance training had] no detrimental effect on linear growth.</p>\n</blockquote>\n\n<p><a href=\"http://www.ncbi.nlm.nih.gov/m/pubmed/16437017\" rel=\"nofollow noreferrer\">http://www.ncbi.nlm.nih.gov/m/pubmed/16437017</a></p>\n\n<p>With all of that, there is the possibility that pushing children in exercise programs without paying attention to rest and nutrition needs could possibly result in growth impairment due to overly high stress levels or malnutrition. However, the basic question of does lifting affect height, the answer is no and it is even recommended.</p>\n\n<p>This was brought together from two excellent answers on the Fitness Stack Exchange site, with <a href=\"https://fitness.stackexchange.com/a/22331\">thanks to Daniel</a> and <a href=\"https://fitness.stackexchange.com/a/22152\">to Eric Kaufman</a>.</p>\n", "score": 6 } ]
4,251
CC BY-SA 3.0
Does lifting weights inhibit growth for teens and kids?
[ "exercise", "weight", "pediatrics" ]
<p>Does lifting weights inhibit growth for teens and kids? Some people I know argue yes, while others argue no. So, I want to know which one is true.</p>
9
https://medicalsciences.stackexchange.com/questions/4335/can-you-cauterize-a-wound-with-gunpowder
[ { "answer_id": 4406, "body": "<p>So this was an interesting one for me, because I never seriously tried to consider it. Most online sources that claim this say it's an \"old army trick,\" but after reading <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2706344/\" rel=\"nofollow noreferrer\">several</a> perspectives on wound care in the <a href=\"https://books.google.com/books?id=ApUwm4KJJFYC&amp;printsec=frontcover&amp;dq=cauterization%20Care%20of%20the%20Combat%20Amputee&amp;hl=en&amp;sa=X&amp;ved=0ahUKEwin_cqQ-6rKAhWIZCYKHewEAx4Q6AEIJjAA#v=onepage&amp;q=cauterization%20Care%20of%20the%20Combat%20Amputee&amp;f=false\" rel=\"nofollow noreferrer\">military</a>, I don't know that is true.</p>\n\n<p>The actual historical roots on this idea I could find actually go back to reference a <a href=\"http://catdir.loc.gov/catdir/enhancements/fy0708/2006049193-s.html\" rel=\"nofollow noreferrer\">slave owner</a> using it as a form of abuse to over work his slave, or a <a href=\"https://newspapers.library.in.gov/cgi-bin/indiana?a=d&amp;d=SBNT19150714.1.13\" rel=\"nofollow noreferrer\">short fiction</a> story from 1915.</p>\n\n<p>The problem is one of timing. As wars started to utilize gun powder more, tourniquets were realized to be superior to cauterization (first ideas of tourniquets go back to ~1500's, serious implantation with Jean Petit in early 1700's). By the time we get to something like Vietnam, not only would the solders have had tourniquets, if they were going to cauterize the wound they would have done it chemically.</p>\n\n<p>Another problem is the gas and force released from igniting gun powder. It doesn't just burn hot, it propels. That's why it's useful for moving bullets. I think this would likely further distort the tissue, and if applied in large amounts in to major arteries/veins, a good deal of toxicity problems.</p>\n\n<p>I just honestly think this would cause more harm than good. I'd be very interested if someone can find a documented example of where this was actually tried in the field (and I missed it). Considering you can't readily treat your own neck, the appropriate thing to do would be to apply direct pressure with your hands to the places that are bleeding the most (or if you're the one helping, then the same to the other person's neck). </p>\n\n<p>Oddly enough I have a <a href=\"https://biology.stackexchange.com/questions/11058/how-to-close-a-severed-artery-vein/11088#11088\">more detailed SE answer</a> written up in Bio, for those interested in proper wound care in the neck.</p>\n\n<hr>\n\n<h2>Edit:</h2>\n\n<p>I was made aware the \"Dual Survival\" episode where one of the characters cauterizes a wound (<a href=\"https://www.youtube.com/watch?v=5LFGE7rGUkA\" rel=\"nofollow noreferrer\">YouTube Video Here</a> and then <a href=\"https://www.youtube.com/watch?v=eerOKfiOuQ4\" rel=\"nofollow noreferrer\">here</a>). You will note that even the survivalist unequivocally rejected this method as valid before he did it to himself (presumably for considerable compensation from Discovery Channel). I reject this as a valid example for the following reasons:</p>\n\n<ol>\n<li><p>That was a shallow wound where the bleeding was mostly controlled, (from the video you can see that it is hardly bleeding), and as a wound caused by a clean cut, could and should be controlled with pressure and binding.</p></li>\n<li><p>You can see that the initial load of gun powder did not ignite, some initial cauterization probably occurred by dropping whatever was on fire onto the cut (looked like moss). Further, as mentioned in the video, the gunpowder was mixing with his blood and stinging, a pretty good sign it was being introduced into his blood stream, which could cause toxicity problems.</p></li>\n<li><p>Because of the shallow nature of this cut, much of the gas released was able to burst out and away from his arm. In a wound actually calling for cauterization, the powder would have had to been placed much deeper. Think of this problem as the difference between igniting black powder on the top of a rock vs packing it into a deep crack. Only one of those leads to an exploding rock. </p></li>\n<li><p>Further, this brings up the problem of technology again. If they had a knife to heat, and were dead set on cauterization, they should have used the heated knife. No additional benefit of gunpowder would be had, and there are several clear drawbacks. As someone who hunts and hikes often, how many times will you be walking around with black powder (not newer gunpowder formulations) without a good knife? Or for that matter, a belt and cloth and the ability to make a tourniquet (even a make-shift one).</p></li>\n</ol>\n\n<p>Again, the wound in the video doesn't even call for a tourniquet, to say nothing of cauterization. This is an example of something that makes sensational TV does not make good medical sense, and probably helps spread medical misconceptions and ignorance (as the premise of the show is to help demonstrate survivalist techniques).</p>\n", "score": 6 } ]
4,335
CC BY-SA 3.0
Can you cauterize a wound with gunpowder?
[ "first-aid", "stitches", "penetrate-trauma-wound", "exsanguination" ]
<p>This question is based off a scene in The Revenant. In it, a character has a deep laceration across their throat which has been hastily stitched up. Upon drinking some water, they find that it passes straight through the stitched-up wound. </p> <p>The solution presented in the film is to rub some gunpowder (assuming period accuracy, this would be early 1800's black powder, not the modern stuff) into the wound and then ignite it. Presumably to seal the wound more completely by cauterizing it.</p> <p>Which leads to my question; are there any documented clinical examples of people cauterizing actual wounds using gunpowder, and if so what was the outcome? Is gunpowder a plausible method of closing a wound if/when no other alternatives are readily available?</p>
9
https://medicalsciences.stackexchange.com/questions/4413/how-much-of-the-difference-in-brain-size-is-attributable-to-gender-not-physical
[ { "answer_id": 4633, "body": "<p>This is an excellent question. In my attempt to answer it I'll cite sources from the best research on the subject to date, and we'll conduct our own investigation.</p>\n\n<h2>Body size vs. Head size vs. Brain volume</h2>\n\n<p>In your question, you asked how body size (weight and height) relates to brain volume by gender. Body size is related to brain volume through another measure, head size. Larger body, larger head, larger brain.<sup><a href=\"http://www.karger.com/Article/Abstract/321192\" rel=\"nofollow noreferrer\">a</a></sup> Men and women have different body sizes, and different head sizes as well. </p>\n\n<hr>\n\n<h2>Conducting our own investigation</h2>\n\n<h3>Sample</h3>\n\n<p>In the paper you referenced, Gur et. al. looked at 80 healthy (40 male and 40 female) volunteers aged 18-45 years. They used an automated parcellation approach, meaning they used automated image processing on the brain images to derive their measurements.</p>\n\n<p>In our investigation, we'll use data frome the publicly available <a href=\"http://www.humanconnectomeproject.org/\" rel=\"nofollow noreferrer\">Human Connectome Project</a>, or HCP. We'll look at 896 healthy (393 Male and 503 female) volunteers aged 22-36 years. HCP also used an automated parcellation software, called FreeSurfer.<sup><a href=\"http://www.sciencedirect.com.scopeesprx.elsevier.com/science/article/pii/S1053811912000389\" rel=\"nofollow noreferrer\">b</a></sup> We'll use IntraCranial Volume - the volume inside the cranium - to represent head size.</p>\n\n<h3>Total Brain Volume - Males vs Females</h3>\n\n<p><a href=\"https://i.stack.imgur.com/a0iRI.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/a0iRI.png\" alt=\"tbv in male vs female\"></a>\n<a href=\"https://i.stack.imgur.com/6Cg4D.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/6Cg4D.png\" alt=\"tbv in male vs female linear model\"></a></p>\n\n<p></p>\n\n<p>We see here that men have larger brains than women. We can also see from the linear model results that the estimated mean difference from our sample is a substantial 153.9 milliliters (as compared to ~200 milliliters in Gur et. al. 2001). For reference, this is about 2/3 one of those half pint boxes of milk you used to get at school lunch.</p>\n\n<p>But how much is total brain volume related to head size?</p>\n\n<h3>TBV vs ICV</h3>\n\n<p><a href=\"https://i.stack.imgur.com/ohjHh.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/ohjHh.png\" alt=\"tbv vs icv\"></a></p>\n\n<p>We can see right away that these two measures are highly correlated. It makes sense. Typically, bigger animals -- with corresponding bigger heads -- have bigger brains:</p>\n\n<p><img src=\"https://upload.wikimedia.org/wikipedia/commons/thumb/1/1b/Brain-body_mass_ratio_for_some_animals_diagram.svg/500px-Brain-body_mass_ratio_for_some_animals_diagram.svg.png\" alt=\"animal brains\"></p>\n\n<p>But what you want to know is whether the difference remains <em>after accounting for head size</em>. In other words, is the difference disproportionate to head size?</p>\n\n<h3>Adjusting TBV by ICV</h3>\n\n<p>Here we use a method called residualizing to remove the effect of ICV on TBV we observed above. You can find the code we're using <a href=\"https://github.com/keshlab/returnAdj.R/blob/master/returnAdj.R\" rel=\"nofollow noreferrer\">here</a>, and a reference describing the procedure in detail <a href=\"http://link.springer.com/chapter/10.1007%2F978-0-585-25657-3_18\" rel=\"nofollow noreferrer\">here</a>.</p>\n\n<p>Let's check the graph of TBV vs ICV again, to make sure the effect is removed.</p>\n\n<p><a href=\"https://i.stack.imgur.com/htsUE.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/htsUE.png\" alt=\"adj tbv vs icv\"></a></p>\n\n<h3>Revisiting TBV in Males vs Females</h3>\n\n<p>Here we'll reexamine the difference between Male and Female brain sizes using the adjusted values.\n<a href=\"https://i.stack.imgur.com/4nJik.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/4nJik.png\" alt=\"adj tbv in male vs female\"></a>\n<a href=\"https://i.stack.imgur.com/aSNaa.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/aSNaa.png\" alt=\"adj tbv in male vs female linear model\"></a></p>\n\n<p>The difference is still statistically significant, but smaller. The linear model estimates the adjusted average difference to be 23.6 milliliters (compared to 153.9 before). Going back to the milk reference, this is about 1/10 the box, or one sip.</p>\n\n<hr>\n\n<h2>Conclusions</h2>\n\n<p>We found that the difference in brain volumes between men and women is partially, but not completely explained by their difference in head sizes.</p>\n\n<p>The difference is smaller, but still there after adjusting. <strong>Now your next question may be, so what?</strong> Do these differences in brain volume explain anything about behavior or ability? That's where papers like the one you referenced come in. </p>\n\n<p>Gur et. al. suggest in their paper that females compensate for smaller total brain volume by having increased gray matter, and therefore more tissue available for computation. Other studies conclude that in order to understand gender differences in cognitive ability, you have to look closer at the parts of the brain that are activated during different tasks.<sup><a href=\"http://www.sciencedirect.com.scopeesprx.elsevier.com/science/article/pii/S0149763413003011\" rel=\"nofollow noreferrer\">c</a></sup></p>\n\n<p>The HCP data could help us test these ideas too, but that's outside the scope of your question.</p>\n", "score": 3 } ]
4,413
CC BY-SA 3.0
How much of the difference in brain size is attributable to gender, not physical size?
[ "neurology", "sexual-diamorphism", "white-matter", "csf-cerebrospinal-fluid" ]
<p>I've been reading <a href="http://www.jneurosci.org/content/19/10/4065.full">a paper</a> regarding the effects of gender on grey matter and white matter, and one passage not directly related to the final result caught my eye:</p> <blockquote> <p>As expected, intracranial volume in milliliters (ml), consisting of parenchyma, ventricles, and sulci (without subarachnoid space), was (mean ± SD) higher for men (1352.2 ± 104.9) than for women (1154.4 ± 85.1): t = 9.26; df = 78;p &lt; 0.0001. The difference (14.6%) falls between the difference in height (8.2%) and weight (18.7%). Total parenchymal volume was 1229.6 ± 106.2 (range, 1033.9–1469.4) in men and 1072.3 ± 71.5 (range, 895.4–1196.0) in women: t= 7.77; df = 78; p &lt; 0.0001.</p> </blockquote> <p>The difference I'm concerned with is in volume. I've done some additional reading, and it seems clear that men have a <em>slightly</em> larger overall brain size than women (though individual variation and the size of specific regions in the brain mean that this is not a hard and fast rule).</p> <p>I'm wondering how much of this difference in brain size is attributable to differences in physical size and how much is attributable to other effects of gender. To be a bit clearer, if a group of men had the same average height and weight as a group of women, would there still be as much of a difference in brain size between genders, or is the majority of this based purely on overall body size?</p> <p>This is in contrast to the primary result of the study, which seemed to draw neurological conclusions that are not directly related to physical size (regarding percentages of white and grey matter and cerebrospinal fluid).</p>
9
https://medicalsciences.stackexchange.com/questions/4426/why-are-carbs-said-to-be-fattening
[ { "answer_id": 11385, "body": "<p><em>Note: This explanation does not concern itself with body health, wellbeing, the ability to follow/sustain the diet short/long term, impact to nervous system or the psychological impact of satiety that low-carb diets can offer. It only concerns itself with the imaginary scenario of two identical subjects following the same total calorie diet but with macro-nutritional differences.</em></p>\n<hr />\n<h1>Are Carbohydrates fattening?</h1>\n<p>The question asks if carbohydrates lead to more fatty mass gain than the other macronutrients: fat and protein (and alchohol), if consumed at the same calorie level.</p>\n<p>To put it another way: <strong>For weight change, does the macro-nutritional profile of a diet affect the rate and total amount of fat mass gained?</strong></p>\n<p>The common tautology employed by people proving that macro-nutritional profile is not important when it comes to weight loss is &quot;a calorie is a calorie&quot;.</p>\n<h1>Evidence For, or &quot;A calorie is a calorie&quot;</h1>\n<p><strong><a href=\"https://www.ncbi.nlm.nih.gov/sites/myncbi/1Luq1wkRjtrQ8/collections/52134261/public/\" rel=\"nofollow noreferrer\">Several metabolic ward studies have shown that there is no difference in weight loss when protein intake was held constant.</a></strong> If you're really looking for a metabolic advantage through manipulating macronutrient, you'd be far better off putting your money on protein. There's actually some evidence that higher intake levels do convey a small metabolic advantage.</p>\n<p>Unsurprisingly, the studies into macronutrient impact on mass change are numerous but by no means perfect. One has to cast a very critical eye over all the conflicting evidence (and mud-slinging) and make their own decision.</p>\n<p>A good meta analysis of the above tautology by the well-respected Buchholz AC &amp; Schoeller DA. concluded that:</p>\n<blockquote>\n<p>...Neither macronutrient-specific differences in the availability of dietary energy nor changes in energy expenditure could explain these differences in weight loss. Thermodynamics dictate that a calorie is a calorie regardless of the macronutrient composition of the diet...</p>\n<p><em>Buchholz AC, Schoeller DA. <a href=\"http://www.ajcn.org/cgi/pmidlookup?view=long&amp;pmid=15113737\" rel=\"nofollow noreferrer\">Is a calorie a calorie?.</a> Am J Clin Nutr. 2004;79(5):899S-906S.</em></p>\n</blockquote>\n<p>This referenced a ward study (amongst others which also concluded the same):</p>\n<blockquote>\n<p>Both the high-carbohydrate and high-protein groups lost weight (-2.2+/-0.9 kg, -2.5+/-1.6 kg, respectively, P &lt;.05) and the difference between the groups was not significant (P =.9).</p>\n<p><em>Sargrad KR, Homko C, Mozzoli M, Boden G. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/15800559\" rel=\"nofollow noreferrer\">Effect of high protein vs high carbohydrate intake on insulin sensitivity, body weight, hemoglobin A1c, and blood pressure in patients with type 2 diabetes mellitus.</a> J Am Diet Assoc. 2005;105(4):573-80.</em></p>\n</blockquote>\n<p>To continue the evidence-train for there being no win in carbs-vs-fat:</p>\n<p>In a 2003 study by Bravata DM, et al. the conclusion was that nutritional-profile really doesn't affect total weight change at a significant level.</p>\n<blockquote>\n<p>There is insufficient evidence to make recommendations for or against the use of low-carbohydrate diets. [...] Among the published studies, participant weight loss while using low-carbohydrate diets was principally associated with decreased caloric intake and increased diet duration but not with reduced carbohydrate content.</p>\n<p><em>Bravata DM, Sanders L, Huang J, et al. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/12684364\" rel=\"nofollow noreferrer\">Efficacy and safety of low-carbohydrate diets: a systematic review.</a> JAMA. 2003;289(14):1837-50.</em></p>\n</blockquote>\n<p>A 2009 study directly comparing the weight loss &quot;fad&quot; diets concluded that provided you reduce calories, the method you do this is not of importance:</p>\n<blockquote>\n<p>Reduced-calorie diets result in clinically meaningful weight loss regardless of which macronutrients they emphasize.</p>\n<p><em>Sacks FM, Bray GA, Carey VJ, et al. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/19246357\" rel=\"nofollow noreferrer\">Comparison of weight-loss diets with different compositions of fat, protein, and carbohydrates</a>. N Engl J Med. 2009;360(9):859-73.</em></p>\n</blockquote>\n<p>A 1996 study also concluded the same thing:</p>\n<blockquote>\n<p>The results of this study showed that it was energy intake, not nutrient composition, that determined weight loss in response to low-energy diets over a short time period.</p>\n<p><em>Golay A, Allaz AF, Morel Y, De tonnac N, Tankova S, Reaven G. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/8561057\" rel=\"nofollow noreferrer\">Similar weight loss with low- or high-carbohydrate diets.</a> Am J Clin Nutr. 1996;63(2):174-8.</em></p>\n</blockquote>\n<p>An Australian study put them head-to-head over 12 months and didn't find a large difference:</p>\n<blockquote>\n<p>Under planned isoenergetic conditions, as expected, both dietary patterns resulted in similar weight loss and changes in body composition. The LC [low carbohydrate] diet may offer clinical benefits to obese persons with insulin resistance. However, the increase in LDL cholesterol with the LC diet suggests that this measure should be monitored.</p>\n<p><em>Brinkworth GD, Noakes M, Buckley JD, Keogh JB, Clifton PM. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/19439458\" rel=\"nofollow noreferrer\">Long-term effects of a very-low-carbohydrate weight loss diet compared with an isocaloric low-fat diet after 12 mo.</a> Am J Clin Nutr. 2009;90(1):23-32.</em></p>\n</blockquote>\n<p>A 2010 study went a step further and did a 2-year study across over 300 participants; patients lost an average of 7 kg or 7% of body weight, and no differences between the 2 groups were found:</p>\n<blockquote>\n<p>Successful weight loss can be achieved with either a low-fat or low-carbohydrate diet when coupled with behavioural treatment.</p>\n<p><a href=\"https://i.stack.imgur.com/PONTI.jpg\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/PONTI.jpg\" alt=\"clearly no difference\" /></a></p>\n<p><em>Foster GD, Wyatt HR, Hill JO, et al. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/20679555\" rel=\"nofollow noreferrer\">Weight and metabolic outcomes after 2 years on a low-carbohydrate versus low-fat diet: a randomized trial.</a> Ann Intern Med. 2010;153(3):147-57.</em></p>\n</blockquote>\n<p>Taking a different view and looking at weight gain, there are fewer studies but the evidence points to the same outcome.</p>\n<blockquote>\n<p>There was no significant difference in fat balance during controlled overfeeding with fat, fructose, glucose, or sucrose.</p>\n<p><em>Mcdevitt RM, Poppitt SD, Murgatroyd PR, Prentice AM. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/10919929\" rel=\"nofollow noreferrer\">Macronutrient disposal during controlled overfeeding with glucose, fructose, sucrose, or fat in lean and obese women.</a> Am J Clin Nutr. 2000;72(2):369-77.</em></p>\n</blockquote>\n<p>This can be also seen in this small 2000 study:</p>\n<blockquote>\n<p>...fat storage during overfeeding of isoenergetic amounts of diets rich in carbohydrate or in fat was not significantly different, and carbohydrates seemed to be converted to fat by both hepatic and extrahepatic lipogenesis</p>\n<p><em>Lammert O, Grunnet N, Faber P, et al. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/11029975\" rel=\"nofollow noreferrer\">Effects of isoenergetic overfeeding of either carbohydrate or fat in young men.</a> Br J Nutr. 2000;84(2):233-45.</em></p>\n</blockquote>\n<p>A important point to note is that dietary fat <em>is</em> what is stored as bodily fat, when a caloric excess is consumed. For dietary carbohydrate to be stored as fat then they must undergo a conversion through 'de novo lipogenesis' which will occur when the carbohydrate portion of someone's diet alone must approach or exceed ones total daily energy expenditure (TDEE). You can read more <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/10365981\" rel=\"nofollow noreferrer\">here</a></p>\n<p>In addition, for a comprehensive primer on insulin and how it functions please check out <a href=\"http://weightology.net/weightologyweekly/index.php/free-content/free-content/volume-1-issue-7-insulin-and-thinking-better/insulin-an-undeserved-bad-reputation/\" rel=\"nofollow noreferrer\">this post</a> on weightology which is summarised in layman on reddit by /u/ryeguy, <a href=\"https://www.reddit.com/r/Fitness/comments/j853z/insulin_an_undeserved_bad_reputation_plus_notes/\" rel=\"nofollow noreferrer\">here</a>.</p>\n<h1>Evidence Against, or &quot;A calorie is not just a calorie&quot;</h1>\n<p>I cannot find evidence to support the opposite viewpoint. However there is criticism of the studies done these are found in the &quot;Dear Sir&quot;'s in the ASfCN/</p>\n<p><a href=\"http://ajcn.nutrition.org/content/80/5/1445.1.long\" rel=\"nofollow noreferrer\">A post</a> by Anssi H Manninen is critical of a Bravata study:</p>\n<blockquote>\n<p>Bravata DM, Sanders L, Huang J. Efficacy and safety of low-carbohydrate diets: a systematic review. JAMA 2003;289:1837-50.</p>\n</blockquote>\n<p>She states that:</p>\n<blockquote>\n<p>...In the true low-carbohydrate group, the mean weight loss in trials was 17 kg, whereas in the higher-carbohydrate group it was only 2 kg. Oddly, the authors did not consider this significant. Only by intermingling the results of trials of low- to medium- and high-carbohydrate diets could the authors have reached the misleading conclusion quoted above.</p>\n</blockquote>\n<p><a href=\"http://ajcn.nutrition.org/content/80/5/1445.2.long\" rel=\"nofollow noreferrer\">In another article Richard Feinman and Eugene Fine</a> dispute the assertation of &quot;a calorie is a calorie&quot; using the first law of thermodynamics by stating that the second law must also be taken into account.</p>\n<h1>Conclusions</h1>\n<blockquote>\n<p><strong>What should I eat for weight loss?</strong></p>\n<p><em>Eat less.</em> Different diets can make this easier, so pick whichever one\nbest fits your lifestyle. Ultimately, you need to reduce your caloric\nintake.</p>\n<p><a href=\"https://examine.com/nutrition/what-should-i-eat-for-weight-loss/\" rel=\"nofollow noreferrer\">https://examine.com/nutrition/what-should-i-eat-for-weight-loss/</a></p>\n</blockquote>\n<p>Many diets, fad or not, do work. This is mainly because they reduce calories.</p>\n", "score": 6 }, { "answer_id": 4589, "body": "<p>Scientists still aren't sure, but <strong>it seems carbohydrates may be easily converted into fat, depending on the form, or promote fat storage through stimulating insulin.</strong></p>\n\n<p><em>Nutrition Science and Applications (2nd E)</em> by Smolin and Grosvenor, in Chapter 4, page 140 covers this question well.</p>\n\n<blockquote>\n <p>Carbohydrates in and of themselves are not “fattening.” They provide 4\n kcalories per gram compared with 9 kcalories per gram provided by fat.\n In fact, it is the fats that we often add to our high-carbohydrate\n foods that increase their kcalorie tally. A medium-sized baked potato\n provides about 160 kcalories, but the 2 tablespoons of sour cream you\n add brings the total to 225 kcalories...</p>\n \n <p>Any energy source consumed in excess of requirements can cause weight\n gain ... even though carbohydrates are not [as] high in kcalories\n [compared to fat], <strong>the type of carbohydrate affects the impact that\n carbohydrates have on body weight</strong>.</p>\n \n <p>Fructose metabolism in the liver favors fat synthesis, which in part\n contributes to fat production. Studies in mice indicate that dietary\n fructose produces a greater increase in body fat than the same amount\n of sucrose [1]</p>\n \n <p>The rationale behind consuming a low carbohydrate diet for weight loss\n is that <strong>foods high in carbohydrate stimulate the release of insulin,\n which is a hormone that promotes energy storage</strong>. It is suggested\n that the more insulin you release, the more fat you will store.\n High-glycemic index foods, which increase blood sugar and consequently\n stimulate insulin release, are therefore hypothesized to shift\n metabolism toward fat storage. <strong>Low-carbohydrate\n diets... cause less of a glycemic\n response and less insulin release, which is suggested to promote fat loss</strong>.\"</p>\n</blockquote>\n\n<p>So there is the possibility that carbs aren't actually that fattening by themselves. It could be just that people eat a lot of fat with their carbs. On the other hand, some studies seem in indicate that high-energy intake through sugary drinks, desserts, and large quantity consumption play a role in fattening. \n<br></p>\n\n<p>[1] US Dept. of Health and Human Services. US Public\nHealth Service. Oral Health in America: A Report of the\nSurgeon General. Rockville, MD: National Institutes of\nHealth, 2000</p>\n\n<p><br>\n<br></p>\n\n<p>The following links may provide more insight. They suggest that carbohydrate intake is indeed correlated with obesity:</p>\n\n<p><a href=\"http://www.hsph.harvard.edu/nutritionsource/carbohydrates/low-carbohydrate-diets/\" rel=\"nofollow\">http://www.hsph.harvard.edu/nutritionsource/carbohydrates/low-carbohydrate-diets/</a>\n<a href=\"http://www.nejm.org/doi/full/10.1056/NEJMoa1200303#t=articleDiscussion\" rel=\"nofollow\">http://www.nejm.org/doi/full/10.1056/NEJMoa1200303#t=articleDiscussion</a>\n<a href=\"http://www.ncbi.nlm.nih.gov/pubmed/22735432\" rel=\"nofollow\">http://www.ncbi.nlm.nih.gov/pubmed/22735432</a><br>\n<a href=\"http://annals.org/article.aspx?articleid=1900694\" rel=\"nofollow\">http://annals.org/article.aspx?articleid=1900694</a></p>\n", "score": 2 }, { "answer_id": 4863, "body": "<p>The reason why some people say this is because consuming carbs causes insulin levels to rise and insulin inhibits fat metabolism. In the opposite case when type 1 diabetic patients don't take insulin (e.g. when they are ill and not eating well), they are at risk of <a href=\"https://en.wikipedia.org/wiki/Diabetic_ketoacidosis\" rel=\"nofollow noreferrer\">diabetic ketoacidosis</a>. This is caused by the fat metabolism going in overdrive due to lack of insulin, the waste products poisoning the body as a result.</p>\n\n<p>However, the mere fact that there exists such a mechanism is not proof that it has a relevant role to play in energy management of the body. There is no clear evidence in favor of low fat or low carb diet for weight loss from trials. Also any result from a trial has to be evaluated on whether the observed weight loss is sustainable. Take e.g. <a href=\"http://www.bbc.com/news/health-31763205\" rel=\"nofollow noreferrer\">this study comparing low fat to low carb diet:</a></p>\n\n<blockquote>\n <p>Cardiologist Dr Aseem Malhotra was concerned about the health impact of such a low-fat diet.\n \"The total fat intake of 7% is way too low for this to be sustainable and would likely lead to nutritional deficiencies for the essential fatty acids and the fat soluble vitamins.\n \"For the best health, even in the short term, eat real unprocessed foods, concentrate on good nutrition and stop counting calories!\"</p>\n</blockquote>\n\n<p>As pointed out by Paparazzi in the comments, we also have to also note that whole grains won't lead to a large insulin spike as simple carbs. Also, simple sugars such as fructose are not going to lead to a sharp insulin spike when consumed from whole foods such as fruits compared to when consumed in refined form, as <a href=\"https://www.youtube.com/watch?v=sHEJE6I-Yl4\" rel=\"nofollow noreferrer\">pointed out here</a>.</p>\n", "score": 2 }, { "answer_id": 24068, "body": "<p>Carbs are not necessarily fattening as many studies comparing low carb diets to one recommended by the FDA with a higher calorie content going to carbs, have found negligible differences in fat loss. Of course, there is another side to the story. The synthesis of adipose tissue is regulated by the level of sugar in the blood, or rather the level of insulin. The reason that the fat loss in a low carb diet is often negligible unless going from a diet of an extreme amount of carbohydrates to one with close to none at all is the fact that all the other sources of energy that your body uses are first converted to sugar. This means that once a person has adapted to a diet of low carbohydrates, their body starts converting fat into sugar. This again balances the scale and makes it slightly harder to lose weight. This is the reasoning behind carb reloading. While this means that carbohydrates can bring your weight up when consumed in high quantities, they are often okay in smaller ones. This, of course, depends on person to person and you should try to try out different diets to find the best fit. If a low-carb diet helps you stay healthy, go give it a shot.</p>\n<p>There is also another part of the story. The consumption of processed carbohydrates, esp. sugar raises the blood sugar in the blood significantly and over a small period. This can lead to insulin resistance, diabetes, and other insulin-related diseases. Therefore, while carbohydrates might not have anything to do with your beer belly or large waistline, the consumption of processed carbohydrates should generally be avoided as they can be the cause of insulin-related diseases, even though they may not have to do anything to do with your waistline.</p>\n<p><strong>References:</strong></p>\n<ul>\n<li><a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3096021/\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3096021/</a></li>\n<li><a href=\"https://pubmed.ncbi.nlm.nih.gov/31098615/?from_term=low+carbohydrate+diet&amp;from_filter=pubt.clinicaltrial&amp;from_filter=pubt.randomizedcontrolledtrial&amp;from_page=3&amp;from_pos=1\" rel=\"nofollow noreferrer\">https://pubmed.ncbi.nlm.nih.gov/31098615/?from_term=low+carbohydrate+diet&amp;from_filter=pubt.clinicaltrial&amp;from_filter=pubt.randomizedcontrolledtrial&amp;from_page=3&amp;from_pos=1</a></li>\n<li><a href=\"https://pubmed.ncbi.nlm.nih.gov/15148063/\" rel=\"nofollow noreferrer\">https://pubmed.ncbi.nlm.nih.gov/15148063/</a></li>\n</ul>\n", "score": 2 } ]
4,426
CC BY-SA 3.0
Why are carbs said to be fattening?
[ "nutrition", "weight-loss", "calories", "carbohydrates" ]
<p>I have friends who are trying to lose weight and they keep saying they can't eat certain foods because it is high in carbs and <em>carbs are fattening</em>.</p> <p>This doesn't make sense to me, I lost weight myself but all I did was look at the calorie content of foods, if it was carbs or anything else it didn't really matter. Although I do find that foods that are high in carbs are generally also high in calories but this doesn't mean that carbs are more fattening does it?</p> <p>Is there any truth in what my friends are saying; that carbs are fattening?</p> <p>But it's not just my friends that are saying this, I've heard that carbs are fattening from many different sources: A quick search on how to lose weight shows multiple results mentioning limiting of carbs in order to lose weight: <a href="http://authoritynutrition.com/how-many-carbs-per-day-to-lose-weight/" rel="noreferrer">1</a> where they say calorie restricted diets do not work, <a href="http://www.bodybuilding.com/fun/is-cutting-carbs-the-key-to-fat-loss.html" rel="noreferrer">2</a> low carb diet lost more weight than low fat group, because they replaced carbs with protein </p>
9
https://medicalsciences.stackexchange.com/questions/4463/does-hyperthyroidism-affect-serotonin-levels
[ { "answer_id": 14015, "body": "<p>Thyroid function and serotonin activity are highly linked. Serotonin stimulates hypothalamic TRH (Thyroid Releasing Hormone) production, leading to an increase in TSH (Thyroid Stimulating Hormone) production from the pituitary.</p>\n\n<p>Serotonin stimulates hypothalamic TRH production which leads to an increase in TSH production from the pituitary. Adequate serotonin production is necessary to maintain thyroid hormone levels. Theoretically, an excess of serotonin may lead to the opposite reaction. For example, excess serotonin can lead to a reduction in dopamine production, which can then lead to an increase in norepinephrine production, leading to an increased stress response and cortisol production.</p>\n\n<p>When your serotonin levels are low, you feel anxious, depressed, and pessimistic, and you might also struggle with sleep problems — all common symptoms associated with hyperthyroidism. </p>\n\n<p>Sources:\n<a href=\"https://www.ncbi.nlm.nih.gov/pubmed/11840307\" rel=\"noreferrer\">https://www.ncbi.nlm.nih.gov/pubmed/11840307</a>\n<a href=\"https://www.ncbi.nlm.nih.gov/pubmed/18208678\" rel=\"noreferrer\">https://www.ncbi.nlm.nih.gov/pubmed/18208678</a></p>\n", "score": 5 } ]
4,463
CC BY-SA 3.0
Does hyperthyroidism affect serotonin levels?
[ "mental-health", "endocrinology", "depression", "thyroid", "hyperthyroid" ]
<p>I have read that hyperthyroidism can cause depression. Is this because of low serotonin levels or is there is another cause? Does this kind of depression need to be checked by a psychiatrist?</p> <p><em>Edit</em> (if it is too broad I can remove this edit): Can depression lead to thyroid hormone fluctuation?</p>
9
https://medicalsciences.stackexchange.com/questions/4570/what-can-the-variability-of-strength-be-between-different-brands-of-supposedly-i
[ { "answer_id": 4573, "body": "<p>The range where the content of the active substance varies by 60% is way to wide in every country.</p>\n\n<p>In most of the world's <a href=\"http://www.merriam-webster.com/dictionary/pharmacopoeia\">pharmacopoeias</a>, both national and international, the allowed variability in the amount of the active substance can be tested either as <strong><em>uniformity of mass</em></strong> or, if the amount of labeled substance is lower than a certain predefined value, as <strong><em>uniformity of content</em></strong>. For certain dosage forms, testing the uniformity of content is a must, no matter the labeled mass of the active substance (e.g. soft capsules filled with emulsions, suspensions or gels).</p>\n\n<p>Pharmacopeias prescribe the testing procedure and the acceptance criteria. Appropriate regulatory authority requests those pharamcopoeial criteria to be met.</p>\n\n<p>As for the <strong>uniformity of mass</strong>, in the European Pharmacopoeia, Ph. Eur. 7.0. (the newest that can be accessed via browser search) the test is given in the monograph <a href=\"http://180.168.103.34:7947/zl/EP7/20905E.PDF\">2.9.5. Uniformity of mass of single-dose preparations</a>. </p>\n\n<blockquote>\n <p><em>Weigh individually 20 units taken at random or, for single-dose preparations presented in individual containers, the contents of\n 20 units, and determine the average mass. <strong>Not more than 2 of\n the individual masses deviate from the average mass by more\n than the percentage deviation shown</strong> in Table 2.9.5.-1 <strong>and none\n deviates by more than twice that percentage</strong>.\n For capsules and powders for parenteral administration,\n proceed as described below.</em> [emph. mine]</p>\n</blockquote>\n\n<p>Content mass of capsules and powders for parenteral administration is weighed by difference (the whole preparation is weighed, than the empty shell/primary package and the difference is the content mass).</p>\n\n<p>The table mentioned states that for tablets, e.g:</p>\n\n<blockquote>\n <ul>\n <li>average mass is 80 mg or less (allowed) percent deviation is 10</li>\n <li>average mass is more than 80 mg and less than 250 mg percent deviation is 7.5</li>\n <li>average mass is 250 mg or more, percent deviation is 5</li>\n </ul>\n</blockquote>\n\n<p>As for the <strong>uniformity of content</strong>, the same source (Ph. Eur. 7.0.) gives the test in the monograph <a href=\"http://180.168.103.34:7947/zl/EP7/20906E.PDF\">2.9.6.Uniformity of content of single-dose preparations</a> where, again, the test and acceptance criteria vary by dosage form. To take tablets as an example, we can look at \"test A\" (for tablets, powders for parenteral administration, ophthalmic inserts, suspensions for injection):</p>\n\n<blockquote>\n <p><em>The preparation <strong>complies</strong> with the test <strong>if each individual content is between 85 per cent and 115 per cent of the average content</strong>. The preparation <strong>fails to comply</strong> with the test <strong>if more than one individual content is outside these limits or if one individual content is outside the\n limits of 75 per cent to 125 per cent of the average content</strong>.\n If one individual content is outside the limits of 85 per cent to\n 115 per cent but within the limits of 75 per cent to 125 per cent,\n determine the individual contents of another 20 dosage units\n taken at random.The preparation complies with the test if not\n more than one of the individual contents of the 30 units is\n outside 85 per cent to 115 per cent of the average content and\n none is outside the limits of 75 per cent to 125 per cent of the\n average content.</em> [emph. mine]</p>\n</blockquote>\n\n<hr>\n\n<p>As for the other countries, the European pharmacopoeia also gives the test for <a href=\"http://180.168.103.34:7947/zl/EP7/20940E.PDF\">Uniformity of dosage units</a> in monograph 2.9.40. This test (or most of it) was harmonized between the three pharmacopoeias Ph. Eur. (European), USP (for the US) and JP (Japanese). This test is slightly more complicated than the previous, because it calculates the <em>acceptance value</em> based on the mean of the measured samples, standard deviation of these measurements and a coefficient based on the number of measurements. There are 6 different cases of this formula, but the simplest one is where the acceptance value is the standard deviation multiplied by the given coefficient. <strong>This value should not be greater than 15% of the prescribed content</strong>. </p>\n\n<p>Regulatory authorities in these countries acknowledge this harmonisation, see the documents issued by <a href=\"http://www.ema.europa.eu/docs/en_GB/document_library/Scientific_guideline/2009/09/WC500002775.pdf\">EMeA</a> and <a href=\"http://www.fda.gov/downloads/drugs/guidancecomplianceregulatoryinformation/guidances/ucm085364.pdf\">FDA</a>.</p>\n\n<hr>\n\n<p>So, finally, which of these is to be used in Europe? EMeA <a href=\"http://www.ema.europa.eu/ema/index.jsp?curl=pages/regulation/general/quality_qa_part1.jsp&amp;mid=WC0b01ac05801bf0c2#section9\">states</a>:</p>\n\n<blockquote>\n <p>[...] <em>the decision on what approach to take is left to the applicant.</em></p>\n \n <hr>\n</blockquote>\n\n<p>In the U.S. most of the tests are harmonised, and all are given in the USP, monograph <a href=\"http://www.usp.org/sites/default/files/usp_pdf/EN/USPNF/2011-02-25905UNIFORMITYOFDOSAGEUNITS.pdf\">905 Uniformity of dosage units</a>.</p>\n", "score": 7 }, { "answer_id": 4574, "body": "<p>Country - United States</p>\n\n<p>While theoretically possible, a consistent variance of 30% is highly unlikely and it is probable that the actual variance will vary from brand to brand, as well as from production facility to production facility, as well as from batch to batch. The FDA (Food and Drug Administration) mandates a high standard of quality for inspection and adjusts its actual allowed variance based on multiple criteria, including the severity of the effects of a discrepancy in dosage. </p>\n\n<p>Variability is viewed through two perspectives. The rate of absorption and the extent of absorption. These two rates are compared to associated brands of similar medications and within that a difference of 20% is considered significant by the FDA and so a range of approximately 80% to 125% is used for the acceptable window. While this does suggest that a medication can vary by 45% from another brand, the FDA requires that the ratios of the rate and extent both fall within the window as well as a 90% confidence interval to be considered equivalent to another brand. Although theoretically any can vary by a large percentage, if these requirements are met then the practical effect by variance will remain low. Typically, the actual percentage of difference is closer to 10%.</p>\n\n<p>Some further reading:</p>\n\n<ul>\n<li><a href=\"http://www.medscape.com/viewarticle/762343_3\" rel=\"noreferrer\">An interview on bioequivalence with Dr. Robert Howland, MD</a></li>\n<li><a href=\"http://www.fda.gov/drugs/resourcesforyou/consumers/buyingusingmedicinesafely/understandinggenericdrugs/ucm167991.htm\" rel=\"noreferrer\">FDA - A pamphlet on the effects of generic drugs versus brand names</a></li>\n<li><a href=\"http://www.fda.gov/ohrms/dockets/ac/05/briefing/2005-4137B1_07_Nomenclature.htm\" rel=\"noreferrer\">FDA - A docket explaining terms and procedures for comparison of similar medications.</a></li>\n<li><a href=\"http://www.fda.gov/ohrms/dockets/ac/04/slides/4034S2_07_Haidar.ppt\" rel=\"noreferrer\">FDA - A rather terrific powerpoint on variance regulations in the U.S. as well as the criteria used by other countries. It also has a few graphs demonstrating the allowed window of 80%-125%</a></li>\n</ul>\n", "score": 5 }, { "answer_id": 31234, "body": "<p>Generic drugs do not need to conduct the same phase-3 clinical trials as the initial registration studies, instead they have to meet a few requirements (same active ingredient, same drug concentration etc.) and then show <strong>bioequivalence</strong>.</p>\n<p>Lucky has already provided a good overview regarding the accuracy of the concentration of the active ingredient. Rather more important, and where the +/-30% misconception comes from, is the bioequivalence; meaning how much of the active ingredient ends up in the system of the individual.</p>\n<p>The criterion for approval of a generic drug by <a href=\"https://www.fda.gov/media/70958/download\" rel=\"noreferrer\">the FDA</a>, <a href=\"https://www.ema.europa.eu/en/documents/scientific-guideline/guideline-investigation-bioequivalence-rev1_en.pdf\" rel=\"noreferrer\">the EMA</a>, the TGA and WHO is that the 90% confidence interval of all key pharmacological parameters (maximum blood concentration, total blood concentration) must lie within 80% to 125% of the original drug.</p>\n<p>This is where the +/- 30% misconception comes from. However, as this is a confidence interval, it does not mean that the average of the data can be +/-30% of the original drug - as there is variation in human data even the identical drug will have a larger confidence interval than its average.</p>\n<p>In fact, the average difference of key pharmacological parameters between approved branded and generic drugs has been assessed retrospectively, <a href=\"https://pubmed.ncbi.nlm.nih.gov/19776300/\" rel=\"noreferrer\">and is around 4%</a>, which is similar to batch differences within the same drug.</p>\n<p>Only 3% of drugs had an average difference larger than 10%, and those are drugs where a large intra- and interindividual variety is known (ibid.)</p>\n", "score": 5 } ]
4,570
CC BY-SA 4.0
What can the variability of strength be between different brands of supposedly identical medications?
[ "medications", "prescription", "dosage", "legal" ]
<p>I remember reading that medications are within allowable specs if they contain +/- 30% of the labelled strength. I can't find the source of that information in order to check its validity.</p> <p>If that is the case, a 100mg pill would be considered to be within allowable tolerances if it has 70-130mg of the active ingredient.</p> <p>This could mean a 60% change in active ingredient if a patient switches from one brand to another, or if a manufacturer changes its manufacturing process.</p> <p>What is the allowed variability for prescription medications?</p> <p><em>I imagine the law/rule could be different for every country, so please specify for which country your answer applies.</em></p>
9
https://medicalsciences.stackexchange.com/questions/4613/3-injections-for-hep-b-vaccine
[ { "answer_id": 4622, "body": "<blockquote>\n <p><strong>Why is the Hepatitis B vaccine split into 3, any what is the blood test for at the end?</strong></p>\n</blockquote>\n\n<p><em>The answer to this is really no different than this same question about any other vaccine that is given in multiple doses. I'll quote some good points and sources below but understanding how vaccines work in general first, and then getting information on the others questions will give you the best understanding and answer to your question.</em></p>\n\n<blockquote>\n <h2><a href=\"http://www.livescience.com/32617-how-do-vaccines-work.html\" rel=\"nofollow\">How Vaccines Work</a> <sub>(1)</sub></h2>\n \n <p>According to the <strong>Children's Hospital of Philadelphia Vaccine Education Center</strong>, vaccines are made of dead or weakened antigens. They\n can't cause an infection, but the immune system still sees them as an\n enemy and produces antibodies in response. After the threat has\n passed, many of the antibodies will break down, but immune cells\n called memory cells remain in the body.<sub>(1)</sub></p>\n \n <p>When the body encounters that antigen again, the memory cells produce\n antibodies fast and strike down the invader before it's too late.<sub>(1)</sub></p>\n</blockquote>\n\n<hr>\n\n<p><strong>Why is the Hepatitis B vaccine split into 3 doses?</strong></p>\n\n<p>The human body's immune system (and everyone's is different) needs to program itself at the molecular level to build antibodies for fighting off future [antigens] bugs with similiar biomolecular signatures. Medical studies suggest that it's just more efficient to give people two or three doses to ensure the body builds all it needs to at the immune system level to fight these bugs with matching signatures moving forward rather testing all that have been vaccinated to only revaccinate those found that need more than one dose.</p>\n\n<blockquote>\n <h2><a href=\"http://www.huffingtonpost.com/2015/02/07/more-than-one-dose-vaccines_n_6632776.html\" rel=\"nofollow\">Why Some Vaccines Require More Than One Dose</a><sub>(2)</sub></h2>\n \n <p>Every vaccine ever created has to take many variables into\n consideration, he explained, including the individual pathogen or bug;\n how our immune systems respond to it; what parts of the bug can be\n used to generate an immune response that is protective in nature; and\n also how long that response will last. Because that equation is\n notably complex, sometimes a second (or third) dose is a good idea.<sub>(2)</sub></p>\n \n <p>\"Sometimes, if you take a large group of people with one vaccination\n you might expect 90 percent [to be protected],\" he said. \"But if you\n give a second dose, you may get up to 98 percent.\" Rather than testing\n the population to find the 10 percent not protected by the first dose,\n \"what is probably a more straightforward strategy is just giving two\n doses to insure you have that high level of protection,\" he said.<sub>(2)</sub></p>\n</blockquote>\n\n<hr>\n\n<p><strong>What is the blood test for at the end?</strong></p>\n\n<p>Essentially, the test afterwards confirms that you indeed have the antibodies in your blood to fight off the Hepatitis B virus so your immune system will know to attack it when it's signature is matched since the vaccine programmed your immune system to do so.</p>\n\n<blockquote>\n <h2><a href=\"http://www.hepb.org/pdf/vaccine.pdf\" rel=\"nofollow\">How can I tell if I am protected against hepatitis B?</a><sub>(3)</sub></h2>\n \n <p>If someone has received the hepatitis B vaccine, then a simple blood\n test can tell whether they are protected If they have responded to the\n vaccine series, the blood test will show a positive result for the\n hepatitis B surface antibody (HBsAb+). It is recommended that all\n health care workers and household members or sexual partners of an\n infected individual have their antibody levels tested one month after\n completing the vaccine series.<sub>(3)</sub></p>\n</blockquote>\n", "score": 6 } ]
4,613
CC BY-SA 3.0
3 Injections for Hep B Vaccine
[ "vaccination" ]
<p>It has been suggested by my employer that i should get the Hepatitis B vaccine to protect myself.</p> <p>I have had two of the three parts, but this is the first time i have had a vaccine in more than one session.</p> <p>The vaccine is in 3 doses, each around a month apart, followed up by a blood test.</p> <p>Why is the Hepatitis B vaccine split into 3, any what is the blood test for at the end?</p>
9
https://medicalsciences.stackexchange.com/questions/4618/effect-of-antibiotics-on-breastfed-infant
[ { "answer_id": 14299, "body": "<p>It would appear that breast feeding allows the infant gut flora to rapidly normalize after the course of antibiotics whereas this can be a problem for artificially fed infants who can suffer with post antibiotic diarrhoea.</p>\n<blockquote>\n<p>Savino et al., (2011) studied the gut bacteria of exclusively-breastfed infants, with an average age of 4 months, who were admitted to hospital with pneumonia and treated with the antibiotic, ceftriaxone. As expected, they found a negative effect of antibiotic exposure on faecal bacterial numbers with 5 days of antibiotics significantly reducing faecal bacteria to the point where Lactobacilli were undetectable.</p>\n<p>In these exclusively-breastfed infants, faecal bacterial counts returned to pre-antibiotic levels by 15 days after the end of antibiotic treatment. This reflected a rapid reestablishment of commensal bacteria in the infant’s gut. Importantly, there was also no change in stool frequency and no antibiotic-associated diarrhoea in these infants which is a common problem when artificially-fed infants are exposed to antibiotics</p>\n<p>Despite being given doses of an antibiotic which has a detrimental effect on gut bacteria, these exclusively-breastfed infants did not suffer from antibiotic-associated diarrhoea and this finding was attributed to exclusive breastfeeding (Savino et al., 2011).</p>\n</blockquote>\n<p>Unrelated to the question, breastfed infants also appear to need fewer courses of antibiotics.</p>\n<p><a href=\"https://www.breastfeeding.asn.au/feature-article_breastfeeding-and-antibiotics\" rel=\"noreferrer\">https://www.breastfeeding.asn.au/feature-article_breastfeeding-and-antibiotics</a></p>\n", "score": 5 }, { "answer_id": 14327, "body": "<p>Breast milk is known to provide many benefits to the newborn and developing infant. \n According to '<a href=\"https://www.ncbi.nlm.nih.gov/pubmed/27234410\" rel=\"nofollow noreferrer\">Bioactive Proteins in Human Milk: Health, Nutrition, and Implications to Infant Formulas.</a>’:</p>\n\n<blockquote>\n <p>Several proteins in breast milk, including lactoferrin, α-lactalbumin, milk fat globule membrane proteins, and osteopontin, have been shown to have bioactivities that range from involvement in the protection against infection to the acquisition of nutrients from breast milk. </p>\n</blockquote>\n\n<p>Research suggests that breastmilk can help re-establish a healthy balance of bacteria and antibodies <em>even after the use of antibiotics</em>. As stated in '<a href=\"https://www.ncbi.nlm.nih.gov/pubmed/7825464\" rel=\"nofollow noreferrer\">Early infant feeding and micro-ecology of the gut.</a>': </p>\n\n<blockquote>\n <p>Newborn infants are rapidly colonized by both aerobic and and anaerobic bacteria, initially with about 50% of each type. Several factors related both to the infant and its environment influence the composition of the intestinal microflora quantitatively as well as qualitatively. Major ecological disturbances are observed in newborn infants treated with antimicrobial agents. <strong>One way of minimizing the ecological disturbances, which may be seen in infants treated in neonatal intensive care units, is to provide them with fresh breast milk from their mothers and to use antimicrobial therapy only under strict clinical indications</strong>.</p>\n</blockquote>\n\n<p>'<a href=\"https://www.ncbi.nlm.nih.gov/pubmed/10645469\" rel=\"nofollow noreferrer\">Protective nutrients and bacterial colonization in the immature human gut.</a>' describes the role breastfeeding has on infant intestinal microflora. </p>\n\n<blockquote>\n <p>The normal human microflora is a complex ecosystem that is in part dependent on enteric nutrients for establishing colonization. The gut microbiota are important to the host with regard to metabolic functions and resistance to bacterial infections. At birth, bacterial colonization of a previously germ-free human gut begins. Diet and environmental conditions can influence this ecosystem. A breast-fed, full-term infant has a preferred intestine microbiota in which bifidobacteria predominate over potentially harmful bacteria, whereas in formula-fed infants, coliforms, enterococci, and bacteroides predominate. The pattern of bacterial colonization in the premature neonatal gut is different from that in the healthy, full-term infant gut. Those infants requiring intensive care acquire intestinal organisms slowly, and the establishment of bifidobacterial flora is retarded. A delayed bacterial colonization of the gut with a limited number of bacterial species tends to be virulent. Bacterial overgrowth is one of the major factors that promote bacterial translocation. The aberrant colonization of the premature infant may contribute to the development of necrotizing enterocolitis. <strong>Breastfeeding protects infants against infection. Oligo-saccharides and glycoconjugates, natural components in human milk, may prevent intestinal attachment of enteropathogens by acting as receptor homologues. Probiotics and prebiotics modulate the composition of the human intestinal microflora to the benefit of the host. These beneficial effects may result in the suppression of harmful microorganisms, the stimulation of bifidobacterial growth, or both.</strong> In the future, control and manipulation of the bacterial colonization in the neonatal gut may be a new approach to the prevention and treatment of intestinal infectious diseases of various etiologies.</p>\n</blockquote>\n\n<p>While it is possible that the antibiotic your son is taking can impact his gut flora, it is also important to note that breast milk contains a host of factors that can assist in re-establishing a healthy balance.</p>\n", "score": 5 } ]
4,618
CC BY-SA 4.0
Effect of antibiotics on breastfed infant
[ "antibiotics", "pediatrics", "infant", "breastfeeding", "gut-microbiota-flora" ]
<p>My 9-month old son has been diagnosed with mild bronchiolitis and prescribed 5 days of Azithromycin (not so much to cure a virus-induced bronchiolitis, but in order to prevent possible pneumonia).</p> <p>Taking aside an obvious concern on prescribing antibiotics for a mild disease (and i have already heard wildly conflicting opinions on this from fellow pediatricians, to the point of me being completely confused), my question is this:</p> <p><strong>How does breastfeeding impact the negative influence of antibiotics on the infant body, e.g. gut flora? Are there any studies made?</strong></p> <p>Thanks!</p>
9
https://medicalsciences.stackexchange.com/questions/4879/is-decaffeinated-coffee-a-diuretic
[ { "answer_id": 4880, "body": "<p>While coffee in large amounts can stimulate urine production, it's not enough to produce a dehydration effect, especially in people accustomed to drinking caffeine.</p>\n<p><a href=\"http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0084154\" rel=\"noreferrer\">This recent study</a> compared 50 male coffee drinkers in short trials both with and without caffeine, and concluded that in coffee accustomed males, coffee had much the same hydrating effects as drinking straight water.</p>\n<p><a href=\"http://www.ncbi.nlm.nih.gov/pubmed/19774754\" rel=\"noreferrer\">A study review</a> on 36 years worth of caffeine and tea studies also concluded that caffeine consumption does not lead to excess fluid loss.</p>\n<p>The two relevant summaries:</p>\n<blockquote>\n<p>METHOD:</p>\n<p>A literature search was performed using the Medline database of articles published in the medical and scientific literature for the period of January 1966-March 2002. Subject headings and key words used in this search were: tea, coffee, caffeine, diuresis, fluid balance and water-electrolyte balance. A secondary search was performed using the bibliographies of publications identified in the initial search.</p>\n</blockquote>\n<p>And from the same review:</p>\n<blockquote>\n<p>CONCLUSION:</p>\n<p>The most ecologically valid of the published studies offers no support for the suggestion that consumption of caffeine-containing beverages as part of a normal lifestyle leads to fluid loss in excess of the volume ingested or is associated with poor hydration status. Therefore, there would appear to be no clear basis for refraining from caffeine containing drinks in situations where fluid balance might be compromised.</p>\n</blockquote>\n<p>Now to the caffeine itself:\n<a href=\"http://link.springer.com/article/10.1007/s00726-006-0363-5\" rel=\"noreferrer\">This study examined</a> energy drinks, specifically caffeine and taurine, and concluded that the diuresis was largely controlled by the caffeine, as taurine by itself did not produce the same effects.</p>\n<p>The diuretic effect of caffeine is noted in larger amounts, usually the amount found in 3-6 cups of coffee (Depending on how accustomed the individual is to the effect), or 8-10 cups of tea. While decaffeinated coffee still has some residual caffeine, it would not be enough to have the same effect as fully caffeinated drinks.</p>\n<p>As far as the excretion of other substances, <a href=\"http://www.sciencedirect.com/science/article/pii/S0271531784801323\" rel=\"noreferrer\">this study</a> examined the effect of caffeine on excretion of certain elements (calcium, sodium, magnesium and potassium), with the conclusion that all but potassium had higher urinary output levels after caffeine consumption. I am uncertain how that would relate to cardiac function and blood pressure, however.</p>\n", "score": 6 } ]
4,879
CC BY-SA 3.0
Is decaffeinated coffee a diuretic?
[ "blood-pressure", "hydration", "coffee", "urination", "diuretics" ]
<p>Caffeine is a known diuretic, stimulates urine production, and I have even seen "potential dehydration" as one of the arguments in the perennial "is coffee good or bad" debate. It also changes blood pressure, although I don't know if it is only through dehydration or if it has more direct effects on the cardiovascular system. </p> <p>But coffee has many more active substances than just caffeine. What effect does the drinking of coffee have on fluid balance in the body? How does it influence urine excretion, the excretion of other fluid-influencing substances such as salt, is it related to blood pressure, does it change the levels of blood pressure regulating hormones (vasopressin, angiotensin, etc.)? Or are all such effects of coffee purely based on its caffeine content? </p>
9
https://medicalsciences.stackexchange.com/questions/4894/is-it-possible-to-change-persons-blood-group
[ { "answer_id": 4899, "body": "<p>Yes, it is possible. In a bone marrow transplant, all of the patient's bone marrow is destroyed and replaced with donor marrow. Since red blood cells are created by bone marrow, the donor's blood type will determine which type of red cells are produced, as explained <a href=\"http://www.nationalcmlsociety.org/faq/stem-cellbone-marrow-transplant\">here</a>:</p>\n\n<blockquote>\n <p>Does my blood type change after SCT or BMT?</p>\n \n <p>Yes. The recipients blood type eventually changes to the donor type. \n That means if you had a blood type of A+ prior to transplant and your\n donor had a blood type of O, eventually your blood type would become\n O. I may take several weeks, possibly months for your original blood\n type to disappear, but eventually it will.</p>\n</blockquote>\n\n<p>There is also <a href=\"http://www.smh.com.au/news/national/transplant-girls-blood-change-a-miracle/2008/01/24/1201157559928.html\">one report</a> of an Australian girl whose blood type changed following a liver transplant. That appears to have been a unique event, but it does indicate that it is possible by means other than marrow transplant.</p>\n", "score": 8 } ]
4,894
CC BY-SA 3.0
Is it possible to change person&#39;s blood group?
[ "blood", "blood-type", "dna" ]
<p>Is it possible to change person's blood group?</p> <p>I know it is not possible to change person's DNA, so what about blood group?</p>
9
https://medicalsciences.stackexchange.com/questions/4919/how-do-they-make-sure-someone-has-really-died-before-declaring-them-dead
[ { "answer_id": 4931, "body": "<p>You are correct that this happens. It is infrequent (there are not \"many\", as you say, compared to true deaths), but it occasionally happens that someone - even in a hospital - is thought to be dead when they are not actually dead. In one of your stories, the girl was presumed to be <em>brain dead</em>, not dead. So strike that one. Hypothermia is a beast all unto itself, and declaring a cold person dead is a bit tricky.*</p>\n\n<p>Determining death is not simple. The International Guidelines for the Determination of Death – Phase I (May 30-31, 2012) Montreal Forum Report is 46 pages long and it still doesn't have a definitive conclusion.</p>\n\n<p>For the most part (and to simplify a bit), death is determined to have occurred when someone is exceedingly unlikely (determined from experience of millions of deaths) to regain function of their heart. It can be from a very wide variety of causes, but basically it follows cardiac arrest or respiratory arrest leading to cardiac arrest.</p>\n\n<p>The procedure is to observe the patient carefully. In hospital, that usually includes electronic monitors of one sort or another. Out of hospital it's by observation. When there is no evidence of cardiac electrical activity capable of generating a pulse, the patient has not been breathing for some time, oxygenation of blood has fallen to beyond critical levels, and there is no neurological activity, they are pronounced dead.**</p>\n\n<blockquote>\n <p>How do the medical teams or doctors determine then that this person won't all of sudden get a heart beat back? </p>\n</blockquote>\n\n<p>They \"know\" because of the combined observations of millions of deaths before that one. Since it has happened, clearly it <em>might</em> happen, but once all the criteria are met, it means they are clinically dead. The exceedingly vast majority of people observed to be clinically dead are, indeed, dead (no possibility to regain function.) There's nothing else to do.</p>\n\n<p>It is roughly estimated from the <a href=\"http://www.who.int/mediacentre/factsheets/fs310/en/index2.html\" rel=\"noreferrer\">WHO</a> that about 56 million people die every year. Yet it is not every day that someone who was thought to be dead is not, or it wouldn't make the news. Lets be <em>really</em> generous and say it happens once a month somewhere in the world - 12 times a year - and I think this is very, very generous (there is no known number. I'm guessing it's less in industrialized nations.) </p>\n\n<p>That would mean a death diagnostic accuracy rate of at least 99.9999786% (55,999,988 true deaths in 56,000,000 diagnosed deaths.) That is very, very accurate. It is incredibly difficult and expensive to improve on 99.9999786% of anything for a very small return numerically speaking. It sounds harsh, but it's not. It's what society accepts, including you. If you don't believe me, try to get someone to pass a law changing that.</p>\n\n<p>A better question might be <em>why does this happen?</em> It happens because sometimes a heartbeat is so weak as to be imperceptible to the touch, to sound, and even electronically. The person does not appear to be breathing <em>at all</em>. They have no reflexes to demonstrate neuronal activity (for example, the pupil size doesn't change on shining a light into their eyes.) In the days before burial, that doesn't change 99.9999786% of the time. But if someone's metabolic rate is low enough, they might just survive (being cold increases the chances of this*) and the heart might just start getting stronger and they might just wake up. But the odds of that are so extraordinarily low that the increased expense of storing the body, and checking it again in a more advanced state of decomposition, in addition to the increased risk of contagion... it just doesn't happen, because when someone is declared dead, they are dead 99.9999+% of the time. </p>\n\n<p>The whole situation is frightening to some people. But it's really an irrational fear.</p>\n\n<p>To put the \"risk\" in more understandable terms - because the difference between life and death are pretty important - in 2013 in the US, there were 16,121 homicides. About 20% of those are stranger on stranger homicides (that is, not domestic violence, gang related, etc.). That means of 316,000,000 people in the US that year, about 3,225 people were killed by someone unknown to them, or one in 97,984. That's much higher than 12 in 56 million (which is roughly one in 4,670,000). Yet, though it's more common, you probably still leave your house most days not worrying that you'll be killed in that year. It's an acceptable risk, though death by firearm at a stranger's hand is never acceptable.</p>\n\n<p>If this is an unacceptable risk to you (I'm not being sarcastic; it is an acceptable risk for me personally), you should stipulate in your will your wishes to be kept in storage and reexamined intermittently over a period of several days longer than usual for signs of life, and include the funds to do this.</p>\n\n<p>*<sub>In medicine, we have a saying, \"They aren't dead until they're <em>warm and dead.</em>\" It may seem callous to a reader, but it is precisely to avoid the scenario of which you speak, because someone with a decreased temperature can survive anoxic injury better. In fact, cooling someone down who is in cardiac arrest is not uncommon, and cooling after resuscitation is common.</sub></p>\n\n<p>**<sub>Often it is a nurse who discovers someone has died, but in many states, only a doctor, paramedic, or a coroner can declare someone dead. Nurses are often allowed to declare someone dead who is in a nursing home, hospice or a home care patient. Usually (but there is no law) we feel for pulses at various points on the body, we listen for heart sounds with a stethoscope, we listen for breath sounds, we look for chest movement, and I shine a light in the person's eyes looking for a neurological response. If after a few minutes of observation, nothing has been found, the patient is then pronounced.</sub></p>\n\n<p><sub><em>The International Guidelines for the Determination of Death – Phase I May 30-31, 2012 Montreal Forum Report</em> available in full online in PDF</sub><br>\n<sub><a href=\"http://www.columbiamedicinemagazine.org/webextra/spring-2013/node%3Atitle%5D-11\" rel=\"noreferrer\">\"I Pronounce This Patient Dead\"</a> shows that it's not easy even for doctors</sub><br>\n<sub><a href=\"http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0012557/\" rel=\"noreferrer\">Cooling the body after resuscitation following cardiac arrest</a></sub><br>\n<sub><a href=\"http://www.cdc.gov/nchs/fastats/homicide.htm\" rel=\"noreferrer\">All homicides</a> CDC</sub></p>\n", "score": 10 }, { "answer_id": 11818, "body": "<h2>Disclaimer</h2>\n\n<blockquote>\n <p><code>anongoodnurse</code> has provided an <a href=\"https://health.stackexchange.com/questions/4919/how-do-they-make-sure-someone-has-really-died-before-declaring-them-dead/4931#4931\">excellent answer</a> mostly based on the\n U.S. I will focus on Germany and European countries to provide you\n with a broader view of the topic.<br>\n If you should live in the U.S., this will still matter to you as the <em>medical aspects</em> behind my answer remain the same in the U.S. </p>\n \n <p><strong>Obligatory Disclaimer</strong>: I am not a lawyer!</p>\n \n <p><strong>Obligatory Disclaimer No. 2</strong>: I have a rather dark sense of humour and tried to hold it back as to not offend anyone. Feel free to point out parts that you are uncomfortable with in a comment.</p>\n</blockquote>\n\n<hr>\n\n<h2>Legal Aspects</h2>\n\n<p>You're not dead (yet) when you decease. It is only when a doctor declares you dead that you have officially died. In Germany, only a professional doctor (<a href=\"http://landesrecht.thueringen.de/jportal/?quelle=jlink&amp;query=BestattG%20TH&amp;psml=bsthueprod.psml&amp;max=true&amp;aiz=true#jlr-BestattGTHpP6\" rel=\"nofollow noreferrer\">1</a>) may fill out a death certificate and pronounce you dead. </p>\n\n<p>These are well trained physicians (2) and hardly make any mistakes, especially if it comes to something as important as declaring someone dead. </p>\n\n<p>Unexperienced physicians or similar are not allowed to fill out death certificates for exactly this reason: To prevent living people from being declared dead (3). Also, any doctor making a mistake will probably lose their <em>Approbation</em> (license to be a doctor) and no one really wants to declare a person dead even though they aren't. The doctor will be extra cautious.</p>\n\n<h2>Declaring Someone Dead</h2>\n\n<p>In Germany, additional to the rather obvious check for respiratory arrest, cardiac arrest the doctor has to check for the following three signs of death:</p>\n\n<ol>\n<li><strong>Rigor Mortis</strong> (<em>Stiffness of Death</em>):<br>\nThis is stiffness of the corpse due to post-mortem muscle contraction.\nThe normal reaction between adenosine triphosphate and adenosine diphosphate (ATP and ADP) within the muscle fibres ceases after death and the ATP level in the muscle progressively diminishes. This is accompanied by accumulation of lactic acid and a fall of pH (increase in acidity), which leads to stiffening and firmness. (<a href=\"http://www.encyclopedia.com/medicine/diseases-and-conditions/pathology/rigor-mortis\" rel=\"nofollow noreferrer\">4</a>)(<a href=\"http://www.encyclopedia.com/social-sciences/encyclopedias-almanacs-transcripts-and-maps/rigor-mortis-and-other-postmortem-changes\" rel=\"nofollow noreferrer\">5</a>)(6)</li>\n<li><strong>Livor Mortes</strong> (<em>The blue color of death</em>):<br>\nOnce the heart stops beating, blood collects in the most dependent parts of the body as it is not pumped around by the heart, usually the buttocks and back when a corpse is supine. The skin, normally pink-colored because of the oxygen-laden blood in the capillaries, becomes pale as the blood drains into the larger veins. Within minutes to hours after death, the skin is discolored by livor mortis, or what embalmers call \"postmortem stain,\" the purple-red discoloration from blood accumulating in the lowermost (dependent) blood vessels. (<a href=\"http://www.encyclopedia.com/social-sciences/encyclopedias-almanacs-transcripts-and-maps/rigor-mortis-and-other-postmortem-changes\" rel=\"nofollow noreferrer\">5</a>)(6) </li>\n<li><strong>Decomposition</strong>:<br>\n<em>Yeah, let's actually not get into that too much...</em> Basically, there is autolysis (aseptic breakdown of tissues due to the release of intracellular enzymes) and putrefaction (breakdown of tissue due to bacteria). Both are usually accompanied with a very strong odor. It's hard to be overlooked by anyone! (6)</li>\n</ol>\n\n<h2>What if I'm not sure why this person died?</h2>\n\n<p>On a German death certificate, there are three types of death (<a href=\"http://www.vordruckleitverlag.de/tmp/1602.png.html\" rel=\"nofollow noreferrer\">7</a>):</p>\n\n<ol>\n<li><p><strong>Natural Death</strong>:<br>\nIf the person is 120 years old, has pulmonary embolism, cancer and multiple myocardial infarctions, their death is not too much of a surprise and can be considered natural. This is either the case if there are enough illnesses known to assume multiple organ failures or if all symptoms indicate a certain type of death (e.g. a myocardial infarction).</p></li>\n<li><p><strong>Unnatural Death</strong>:<br>\n<em>First I thought he died due to stress, and then I noticed the knife in his back.</em><br>\nIf a person has multiple gunshots, is lacking a head or some limbs or alternatively has been cut into pieces, well, you're off safe to assume they have died an unnatural death. This triggers immediate call of the police and investigation by the prosecution.</p></li>\n<li><p><strong>Unknown cause of death</strong>:<br>\nIf the physician has, simply put, no idea why this person could have died, they will tick the field with <em>Ungeklärte Todesursache</em>. This will usually lead to medical examinations by an official medical officer and sometimes autopsy if no cause for death can be found. (<a href=\"https://www.aerztekammer-bw.de/10aerzte/40merkblaetter/30leichenschau/ungeklaert.pdf\" rel=\"nofollow noreferrer\">8</a>)</p></li>\n</ol>\n\n<h2>Conclusion</h2>\n\n<p>In Germany, death certificates will only be filled out by highly trained physicians. If they have any doubt on how you have died, why or if you are actually dead, they are forced by law to escalate the problem to the next level (i.e. call the police and a medical officer).</p>\n\n<p>Let's assume all eventualities and you actually are pronounced dead wrongly. What is the problem here? It's not like your being cremated the next day (9). Neither will you be killed to make sure that you are dead, but your body will either be left where it has been to allow relatives to have a last visit or stored somewhere. If you are not dead, you can come back to life and just joyfully announce this to your sobbing relatives. Or, in the most extreme cases, <em>just climb out of the tomb</em> ;).</p>\n\n<hr>\n\n<h2>References</h2>\n\n<p>(1): State Law Thuringen, <a href=\"http://landesrecht.thueringen.de/jportal/?quelle=jlink&amp;query=BestattG%20TH&amp;psml=bsthueprod.psml&amp;max=true&amp;aiz=true#jlr-BestattGTHpP6\" rel=\"nofollow noreferrer\">§6 on Declaring Someone Dead</a> <em>[in German]</em> </p>\n\n<p>(2): In Germany, to be a professional physician one must study human medicine for 12 semesters and work 4 years as a assistant doctor before getting the <em>Approbation</em> (license to be a doctor). Only then after at least 10 years of study they are allowed to fill out death certificates. </p>\n\n<p>(3): On a lighter note, just imagine all the bureaucratic effort to revert the death of a person. The word <code>dead card</code> gets a whole new meaning here. </p>\n\n<p>(4): <a href=\"http://www.encyclopedia.com/medicine/diseases-and-conditions/pathology/rigor-mortis\" rel=\"nofollow noreferrer\">The Oxford Companion to the Body</a>, hosted by encyclopaedia.com</p>\n\n<p>(5): <a href=\"http://www.encyclopedia.com/social-sciences/encyclopedias-almanacs-transcripts-and-maps/rigor-mortis-and-other-postmortem-changes\" rel=\"nofollow noreferrer\">Macmillan Encyclopedia of Death and Dying</a>, hosted by encyclopaedia.com</p>\n\n<p>(6): <strong>Content Warning</strong>: Explicit Images of Corpses.<br>\n Forensic pathology - <a href=\"http://www.pathologyoutlines.com/topic/forensicspostmortem.html\" rel=\"nofollow noreferrer\">General Postmortem changes</a></p>\n\n<p>(7): <a href=\"http://www.vordruckleitverlag.de/tmp/1602.png.html\" rel=\"nofollow noreferrer\">A template for the German death certificate</a> <em>[in German]</em></p>\n\n<p>(8): <a href=\"https://www.aerztekammer-bw.de/10aerzte/40merkblaetter/30leichenschau/ungeklaert.pdf\" rel=\"nofollow noreferrer\">An official guidance</a> to doctors how to fill out a death certificate and what options there are by the state of Baden-Württemberg <em>[in German]</em>. </p>\n\n<p>(9) Interestingly enough, in the U.S. you can actually be <a href=\"http://www.us-funerals.com/funeral-articles/understanding-cremation-laws-and-how-they-affect-arranging-a-cremation.html#.WOO5pRhh2fc\" rel=\"nofollow noreferrer\">cremated after a minimum waiting period</a> of 24 hours or 48 hours (depending on state law).<br>\nIn Germany, there <a href=\"https://www.bestattungen.de/ratgeber/bestattungsarten/feuerbestattung.html\" rel=\"nofollow noreferrer\">has to be a second <em>Leichenschau</em></a> (basically going through the list and checking whether all signs of death are present) at least 48 hours after the official death time.</p>\n", "score": 4 }, { "answer_id": 11813, "body": "<p>Through the collective experience of observing millions of deaths, we have arrived at the following indicators of irrecoverable death, each one a more final proof than the previous:</p>\n\n<ol>\n<li>Respiratory arrest (no breathing)</li>\n<li>Cardiac arrest (no pulse)</li>\n<li>Pallor mortis, paleness which happens in the 15–120 minutes after death</li>\n<li>Livor mortis, a settling of the blood in the lower (dependent) portion of the body</li>\n<li>Algor mortis, the reduction in body temperature following death. This is generally a steady decline until matching ambient temperature</li>\n<li>Rigor mortis, the limbs of the corpse become stiff (Latin rigor) and difficult to move or manipulate</li>\n<li>Decomposition, the reduction into simpler forms of matter, accompanied by a strong, unpleasant odor.</li>\n</ol>\n\n<p>More Information: <a href=\"https://en.wikipedia.org/wiki/Death#Signs\" rel=\"nofollow noreferrer\">https://en.wikipedia.org/wiki/Death#Signs</a></p>\n", "score": 1 } ]
4,919
CC BY-SA 3.0
How do they make sure someone has really died before declaring them dead?
[ "death", "procedural-expectations", "hospital" ]
<p>What is the way they determine someone died before declaring them dead?</p> <p>There are stories I've heard of over the years, people who's heart stopped, were brain dead, fell under ice rivers for half an hour and miraculously survived. So there are many instances of unexplained recoveries.</p> <p>How do the medical teams or doctors determine then that this person won't all of sudden get a heart beat back? </p>
9
https://medicalsciences.stackexchange.com/questions/5144/can-health-be-improved-by-viewing-pictures-or-videos-of-nature-on-the-computer
[ { "answer_id": 20527, "body": "<p>Yes, there is evidence that looking at digital images of nature scenes can positively impact psychological and physical wellbeing. However, I cannot find any evidence relating to harder endpoints such as mortality data. Also note that there is a greater body of evidence for exposure to true nature rather than simply images or digital reconstructions of nature.</p>\n<hr />\n<p><a href=\"http://dx.doi.org/10.1021/es103907m\" rel=\"nofollow noreferrer\">This 2011 UK review</a> on the subject made several interesting points:</p>\n<blockquote>\n<p>Other authors have attempted to demonstrate the human desire for connections with nature by showing test subjects photographs of urban and green environments and asking them to express their preferences for different scenes.</p>\n<p>The presence of trees was strongly associated with feelings of relaxation. Similarly, views of gardens, flowers, and landscaped areas were highly favored.</p>\n</blockquote>\n<p>These show simply a preference for nature images, not necessarily an improvement in health.</p>\n<hr />\n<p><a href=\"https://doi.org/10.3390/ijerph14070752\" rel=\"nofollow noreferrer\">This study</a> tested still and dynamic nature images against other entertainment while subjects ran on a treadmill:</p>\n<blockquote>\n<p>Conclusions: Self-selected entertainment encouraged greater physical\nperformances whereas running in nature-based exercise environments\nelicited greater happiness immediately after running.</p>\n</blockquote>\n<p>This was a small study of just 30 participants, but it does show potential health benefits of nature images.</p>\n<hr />\n<p><a href=\"https://doi.org/10.1016/j.physbeh.2013.05.023\" rel=\"nofollow noreferrer\">This paper</a> (referenced in the National Geographic article) conducted an experiment by inducing stress (a simulated interview) and exploring the physiological outcomes in people recovering in two different virtual natural environments and one control group. They measured cardiovascular data and salivary cortisol.</p>\n<p>There was prasympthetic activation (the arm of the autonomic nervous system responsible for rest and routine functions) in the group subjected to sounds of nature in a virtual natural environment. This suggests that enhanced stress recovery may occur in such surroundings.</p>\n<blockquote>\n<p>The results demonstrate a potential mechanistic link between nature, the sounds of nature, and stress recovery, and suggest the potential importance of virtual reality as a tool in this research field.</p>\n</blockquote>\n<hr />\n<p><strong>Sources</strong>:</p>\n<p><a href=\"http://dx.doi.org/10.1021/es103907m\" rel=\"nofollow noreferrer\">Depledge et al. <strong>Can Natural and Virtual Environments Be Used To Promote Improved Human Health and Wellbeing?</strong> Environmental Science and Technology, 2011.</a></p>\n<p><a href=\"https://doi.org/10.3390/ijerph14070752\" rel=\"nofollow noreferrer\">Yeh et al. <strong>Physical and Emotional Benefits of Different Exercise Environments Designed for Treadmill Running.</strong> International Journal of Environmental Research and Public Health, 2017.</a></p>\n<p><a href=\"https://doi.org/10.1016/j.physbeh.2013.05.023\" rel=\"nofollow noreferrer\">Annerstedt, Währborg. <strong>Inducing physiological stress recovery with sounds of nature in a virtual reality forest — Results from a pilot study.</strong> Physiology and Behavioir, 2013.</a></p>\n", "score": 3 } ]
5,144
CC BY-SA 4.0
Can health be improved by viewing pictures or videos of nature on the computer?
[ "mental-health", "environmental-psychology", "calm-soothing-strategies", "relax-relaxation" ]
<p><em>This Is Your Brain on Nature</em> by Florence Williams, January 2016, National Geographic Magazine<br> (<a href="http://ngm.nationalgeographic.com/2016/01/call-to-wild-text" rel="nofollow noreferrer">published online 2015/12/8</a>)</p> <blockquote> <p>Measurements of stress hormones, respiration, heart rate, and sweating suggest that short doses of nature—or even pictures of the natural world—can calm people down and sharpen their performance. </p> </blockquote> <p>What evidence is there for the assertion above? I am asking this question only with regard to viewing pictures or videos of nature scenes online or on the computer.</p>
9
https://medicalsciences.stackexchange.com/questions/5489/any-scientific-evidence-supporting-positive-effects-from-listening-to-binaural-b
[ { "answer_id": 12842, "body": "<blockquote>\n <p>Is there any peer-reviewed scientific evidence supporting positive effects from listening to binaural beats?</p>\n</blockquote>\n\n<p>Yes, several. Here are two <a href=\"https://en.wikipedia.org/wiki/RSS\" rel=\"nofollow noreferrer\">RSS feeds</a>, which will continuously update, with research articles on binaural beats:</p>\n\n<p><a href=\"https://eutils.ncbi.nlm.nih.gov/entrez/eutils/erss.cgi?rss_guid=1JAk5IMbg5bmNMHPIeQ14XUY1FnnNzZdrT8hIlMftEW8mAyICV\" rel=\"nofollow noreferrer\">PubMed RSS feed</a> - <a href=\"https://www.nlm.nih.gov/pubs/factsheets/pubmed.html\" rel=\"nofollow noreferrer\">PubMed</a> (US National Library of Medicine) where \"binaural beats\" appears in the title or abstract of an article. (\"binaural beats\"[Title/Abstract]) </p>\n\n<p><a href=\"http://www.cochrane.org/rss/binaural%20beats?f%5B0%5D=bundle%3Areview&amp;f%5B1%5D=im_field_stage%3A3&amp;adv=1\" rel=\"nofollow noreferrer\">Cochrane RSS feed</a> - standard search for 'binaural beats'.</p>\n\n<p>This is the only review article I could find:</p>\n\n<p>Chaieb, L., Wilpert, E. C., Reber, T. P., &amp; Fell, J. (2015). Auditory beat stimulation and its effects on cognition and mood states. <em>Frontiers in Psychiatry, 6</em>. <a href=\"https://doi.org/10.3389/fpsyt.2015.00070\" rel=\"nofollow noreferrer\">https://doi.org/10.3389/fpsyt.2015.00070</a></p>\n\n<p>I did not find any articles with a meta-analysis of the extant research.</p>\n\n<p>Several very recent articles add to accumulating evidence for positive effects, under specific conditions, e.g., listening to 15 Hz binaural beats but not 5 Hz binaural beats, and with specific individuals, i.e., not every adult will respond in the same manner depending on several variables, many of which have not yet been delineated. </p>\n\n<h3>Anxiety Reduction</h3>\n\n<p>Isik, B. K., Esen, A., Büyükerkmen, B., Kilinç, A., &amp; Menziletoglu, D. (2017). Effectiveness of binaural beats in reducing preoperative dental anxiety. <em>British Journal of Oral and Maxillofacial Surgery, 55</em>(6), 571–574. <a href=\"https://doi.org/10.1016/j.bjoms.2017.02.014\" rel=\"nofollow noreferrer\">https://doi.org/10.1016/j.bjoms.2017.02.014</a></p>\n\n<h3>Heart-Rate Variability (Relaxation)</h3>\n\n<p>McConnell, P. A., Froeliger, B., Garland, E. L., Ives, J. C., &amp; Sforzo, G. A. (2014). Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal. <em>Frontiers in Psychology, 5</em>. <a href=\"https://doi.org/10.3389/fpsyg.2014.01248\" rel=\"nofollow noreferrer\">https://doi.org/10.3389/fpsyg.2014.01248</a></p>\n\n<h3>Creativity</h3>\n\n<p>Reedijk, S. A., Bolders, A., &amp; Hommel, B. (2013). The impact of binaural beats on creativity. <em>Frontiers in Human Neuroscience, 7</em>. <a href=\"https://doi.org/10.3389/fnhum.2013.00786\" rel=\"nofollow noreferrer\">https://doi.org/10.3389/fnhum.2013.00786</a></p>\n\n<h3>Visuospatial Working Memory</h3>\n\n<p>Beauchene, C., Abaid, N., Moran, R., Diana, R. A., &amp; Leonessa, A. (2016). The effect of binaural beats on visuospatial working memory and cortical connectivity. <em>PLOS ONE, 11</em>(11), e0166630. <a href=\"https://doi.org/10.1371/journal.pone.0166630\" rel=\"nofollow noreferrer\">https://doi.org/10.1371/journal.pone.0166630</a></p>\n\n<h3>Verbal Working Memory</h3>\n\n<p>Beauchene, C., Abaid, N., Moran, R., Diana, R. A., &amp; Leonessa, A. (2017). The effect of binaural beats on verbal working memory and cortical connectivity. <em>Journal of Neural Engineering, 14</em>(2), 026014. <a href=\"https://doi.org/10.1088/1741-2552/aa5d67\" rel=\"nofollow noreferrer\">https://doi.org/10.1088/1741-2552/aa5d67</a></p>\n\n<h3>Cognitive Flexibility</h3>\n\n<p>Hommel, B., Sellaro, R., Fischer, R., Borg, S., &amp; Colzato, L. S. (2016). High-frequency binaural beats increase cognitive flexibility: evidence from dual-task crosstalk. <em>Frontiers in Psychology, 7</em>. <a href=\"https://doi.org/10.3389/fpsyg.2016.01287\" rel=\"nofollow noreferrer\">https://doi.org/10.3389/fpsyg.2016.01287</a></p>\n\n<h3>Individual Differences</h3>\n\n<p>Reedijk, S. A., Bolders, A., Colzato, L. S., &amp; Hommel, B. (2015). Eliminating the attentional blink through binaural beats: a case for tailored cognitive enhancement. <em>Frontiers in Psychiatry, 6</em>, 82. <a href=\"https://doi.org/10.3389/fpsyt.2015.00082\" rel=\"nofollow noreferrer\">https://doi.org/10.3389/fpsyt.2015.00082</a> (\"This suggests that the way in which cognitive-enhancement techniques, such as binaural beats, affect cognitive performance depends on inter-individual differences.\")</p>\n\n<blockquote>\n <p>If so, what types of binaural beats, and what were the positive effects?</p>\n</blockquote>\n\n<p>Please see the articles listed in both RSS feeds. Answering your question with specificity would constitute a review article in itself. ;-)</p>\n\n<blockquote>\n <p>Have any negative effects been documented?</p>\n</blockquote>\n\n<p>Not in recent studies where the technique has become more refined based on previous findings. However, I would caution anyone from running out and buying an binaural beats app or the like, unless you know a lot about the topic; you trust the manufacturer; you do not have any potentially contraindicating audiological, psychiatric, neurological, or cognitive impairments or disorders; and you run it by your physician first. </p>\n", "score": 4 } ]
5,489
CC BY-SA 3.0
Any scientific evidence supporting positive effects from listening to binaural beats?
[ "benefits", "lasting-effects-duration", "meditation" ]
<p>Is there any peer-reviewed scientific evidence supporting positive effects from listening to binaural beats?</p> <p>If so, what types of binaural beats, and what were the positive effects?</p> <p>Have any negative effects been documented?</p>
9
https://medicalsciences.stackexchange.com/questions/5665/human-circadian-rythym-can-we-live-a-36-hour-day-or-for-that-matter-a-48-hour
[ { "answer_id": 10251, "body": "<p>A few studies have been published concerning this topic.<br><br> For example this one: <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1330995/\" rel=\"nofollow noreferrer\"><a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1330995/\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1330995/</a></a><br><br>\nTo my knowledge they all had somewhat similar results:<br></p>\n\n<blockquote>\n <p>Seven solitary subjects, and two groups of four, spent from 5 to 13\n days in an isolation unit without knowledge of time. Three solitary\n subjects and one group of four adopted fairly regular activity habits\n with a period of 25-27 h; one subject adopted a period of 30 h, and\n one of 27 h initially, decreasing to 24-25 h after a few days. One\n group of four awoke roughly every 24 h, after a sleep which was\n alternately about 8 h, or about 4 h and believed by the subjects to be\n an afternoon siesta. Two solitary subjects alternated sleeps of about\n 8 or 16 h, separated by 24 h of activity.</p>\n</blockquote>\n\n<p>So while your 'optimal' rhythm might be somewhere around 25 hours of activity in one circadian cycle, there are severe social implications to consider living in 'another timezone' than everybody else in your community.<br><br>\nConcerning the second part of your question <em>and then sleep for over 16 hours</em>, there are studies, which show that for an average adult the optimal amout of sleep lies between 7-9 hours. However, the test subjects in these studies are usually just awake for around 15 hours. So, I do not think that anybody can give you a responsible advice on this matter.</p>\n\n<p>Also, to my knowledge, there is no reasonable amount of evidence for long-term effects such a changed circadian cycle might have on one's health.</p>\n", "score": 2 } ]
5,665
CC BY-SA 3.0
Human Circadian Rythym, can we live a 36 hour day, or for that matter, a 48 hour day?
[ "sleep", "circadian-rythym" ]
<p>By this I mean, is it possible or advisable to change my rhythm so that I wake up on Monday morning, sleep Tuesday afternoon (I'm awake for over 24 hours) and then sleep for over 16 hours till the Wednesday morning. Can we alter our body clock this way?</p>
9
https://medicalsciences.stackexchange.com/questions/7303/how-does-my-body-know-how-long-a-month-is
[ { "answer_id": 7313, "body": "<p><em>Just as a small background before answering your question</em>: as suggested in the previous answers, <strong>the menstrual cycle is regulated by complex interactions between the hypothalamic-pituitary-ovarian (HPO) axis and the uterus.</strong> The hypothalamus secretes gonadotropin-releasing hormone (<strong>GnRH</strong>), which stimulates the release of follicle stimulating hormone (<strong>FSH</strong>) and luteinizing hormone (<strong>LH</strong>) from the pituitary gland. These so called gonadotropins (LH and FSH) stimulate the ovary to release an oocyte that is capable of fertilisation if it encounters a spermatozoid. In the same time, hormones are secreted by the ovary in response to FSH or LH. These hormones influence the endometrium (= the inner layer of the uterus)</p>\n\n<p>The type of hormones released during the menstrual cycle and their concentration divide a <strong>menstrual cycle in three phases</strong> (see figure below):</p>\n\n<p><a href=\"https://i.stack.imgur.com/OtIb0.png\" rel=\"noreferrer\"><img src=\"https://i.stack.imgur.com/OtIb0.png\" alt=\"enter image description here\"></a></p>\n\n<ul>\n<li><strong><em>the follicular or proliferative phase (D4-D14 of the cycle)</em></strong>: it is\ncharacterised by the recruitment of a cohort of follicles and the\nultimate selection of a “dominant” preovulatory follicle.\nAdditionally, this phase shows increasing levels of estradiol which\nstimulate the proliferation of endometrium. This proliferation takes\ntime (approx 10 days) as cells composing the endometrium replicate\nintensively (mitosis) in order to enhance the thickness of the\nendometrium (remember, the endometrium has to be “prepared” for a\npossible implantation of a blastocyts (= first stage of an\nembryon)). The figure below shows the change in the structure of the endometrium.</li>\n<li><p><strong><em>the luteal or secretory phase (D14-D28):</em></strong> the production of\nprogesterone leads to a differentiation of the endomterium which\nreaches its full maturity. Here again, time is needed, to gain the\nlevel of complexity found in the endometrium of the luteal phase: the\nglands and the arteries in the endometrium begins to entwine, the\nconnective tissue show oedematous changes. Everything is prepared to help the blastocyst to develop in the case of an implantation</p></li>\n<li><p><strong><em>the menstruation phase (D1-D4):</em></strong> when implantation does not occur, the\namounts of estradiol and progesterone drop significantly, leading to\na constriction of the arteries found in the endometrium. This results\nto the expulsion of the so called “functional layer” of the\nendometrium.</p></li>\n</ul>\n\n<p><a href=\"https://i.stack.imgur.com/OnAmp.jpg\" rel=\"noreferrer\"><img src=\"https://i.stack.imgur.com/OnAmp.jpg\" alt=\"enter image description here\"></a></p>\n\n<p>Your question</p>\n\n<blockquote>\n <p>How does my body gauge that amount of time? Is there some kind of\n external factor (wake/sleep cycles, etc) or is there some kind of\n internal timer?</p>\n</blockquote>\n\n<p>Therefore <strong>the duration of the menstrual cycle is defined by the time needed for all these changes to occur</strong>: the proliferation of cells of the endometrium, the development of arteries and the differentiation of glands in the endometrium etc… Similar example would be the time needed for wound healing for example (where the proliferative phase is characterised by fibroblast migration, collagen synthesis, angiogenesis, migration of new cells) or lung tissue recovery after a pneumonia.</p>\n\n<p>Why the duration of cycle is different from one woman to another is dependent, as you have already suggested, on internal factors (the concentration of hormones, the presence of a concomitant chronic disease for example) and external factors (stress, drugs,…)</p>\n\n<p>The body gauges the amount of time necessary for the cycle, ie the time necessary for all the endometrial changes to occur (in a woman: approx 28-32 days) through a complex feedback from the hormones produced in the ovary/endometrium which “signal” the hypothalamus and the pituitary on whether a change in the secretion of LH/FSH should occur or not. <strong>This hypothalamus-pituitary-ovarian (HPO) axis is the “metronome” for the menstruation cycle</strong> (see figure below for an overview of the HPO axis)</p>\n\n<p><a href=\"https://i.stack.imgur.com/oIDnb.png\" rel=\"noreferrer\"><img src=\"https://i.stack.imgur.com/oIDnb.png\" alt=\"enter image description here\"></a></p>\n\n<p>Several studies have investigated the effect of menstruation cycle phases on sleep and reported that menstrual cycle alter sleep organisation at different menstrual phases. Also, disruption of circadian rhythms is associated with disturbances in menstrual function. For example, female shiftworkers compared to non-shiftworkers are more likely to report menstrual irregularity and longer menstrual cycles. This is likely due to a change in the circulating hormone, <em>strengthening the role of “metronome” of the HPO in the time regulation of the menstruation cycle.</em></p>\n\n<p>Sources:</p>\n\n<ul>\n<li>Longo DL, Fauci AS, Kasper DL, Hauser SL, Jameson J, Loscalzo J. eds. Harrison's Principles of Internal Medicine, 18e. New York, NY: McGraw-Hill; 2012. p 3028-3033</li>\n<li>Shechter A, Boivin DB. Sleep, Hormones, and Circadian Rhythms throughout the Menstrual Cycle in Healthy Women and Women with Premenstrual Dysphoric Disorder. International Journal of Endocrinology. 2010;2010:259345</li>\n<li>Baker FC, Driver HS. Circadian rhythms, sleep, and the menstrual cycle. Sleep Med. 2007 Sep;8(6):613-22. Epub 2007 Mar 26.</li>\n<li>www.meducation.net for Figure 2</li>\n</ul>\n", "score": 13 } ]
7,303
CC BY-SA 3.0
How does my body know how long a month is?
[ "reproduction", "menstruation" ]
<p>Every month I get my period. Mine is somewhat irregular, but it's usually between 27-33 days. </p> <p>How does my body gauge that amount of time? Is there some kind of external factor (wake/sleep cycles, etc) or is there some kind of internal timer?</p> <p>I know how I'd make a digital timer, so I'm curious to know how my body's own timer works.</p>
9
https://medicalsciences.stackexchange.com/questions/7556/how-can-i-access-my-medical-records-in-the-united-states
[ { "answer_id": 18676, "body": "<p>Every American patient has a legal right to access their own medical records. The federal law is called “HIPAA”(Health Insurance Portability and Accountability Act of 1996) which is United States legislation that provides data privacy and security provisions for safeguarding medical information. <a href=\"http://HIPAA%20(Health%20Insurance%20Portability%20and%20Accountability%20Act%20of%201996)%20is%20United%20States%20legislation%20that%20provides%20data%20privacy%20and%20security%20provisions%20for%20safeguarding%20medical%20information.\" rel=\"noreferrer\">How to navigate HIPAA is described here in laymen’s terms.</a> <a href=\"https://www.hhs.gov/sites/default/files/righttoaccessmemo.pdf\" rel=\"noreferrer\">Here is a PDF that you can print</a> which summarizes what your rights are under HIPAA Law.</p>\n<p>Each medical entity (hospital, clinic, individual medical provider) that has treated you as a patient has a legal obligation under HIPAA Law to both preserve your medical records, and make them accessible to you as their patient. You can contact them in writing to obtain a copy for yourself (usually for a fee,) or sign a “Consent to Release” form to have them sent from a prior provider to a new one.</p>\n<p>Since each medical provider uses a different record keeping method, there is no single clearinghouse that contains the totality of your medical records. If that is what you need, you will need to contact each entity at which you were a patient.</p>\n<p>Regarding how an ER obtains your medical information and records, this occurs through what medical professionals call “doc-to-doc” exchange: “the HIPAA Privacy Rule permits a health care provider to disclose protected health information about an individual, without the individual’s authorization, to another health care provider for that provider’s treatment of the individual.” <a href=\"http://The%20HIPAA%20Privacy%20Rule%20permits%20a%20health%20care%20provider%20to%20disclose%20protected%20health%20information%20about%20an%20individual,%20without%20the%20individual%E2%80%99s%20authorization,%20to%20another%20health%20care%20provider%20for%20that%20provider%E2%80%99s%20treatment%20of%20the%20individual.\" rel=\"noreferrer\">hhs.gov</a></p>\n<p>There is no specific service I am aware of which can do the work of collecting your health records for you, other than perhaps your lawyer.</p>\n", "score": 8 } ]
7,556
CC BY-SA 3.0
How can I access my medical records in the United States?
[ "medical-records" ]
<p>I've had different insurance providers over the years and gone to different GPs, specialists, urgent care centers, and ERs in different cities. </p> <p>Is there one place I can go or one number I can call to get a complete copy of my medical records? Do I need to remember and call all of the providers individually? How does the hospital obtain your medical records for reference when you go into the ER?</p> <p>If there's no easy way to track down a complete medical history, is there a service that will do it for me for a fee?</p>
9
https://medicalsciences.stackexchange.com/questions/8688/any-benefits-or-harms-for-hair-removal-beyond-possible-aesthetic-reasons
[ { "answer_id": 15090, "body": "<p>Adverse Effects: A study [See Reference] analyzed the literature and did interviews with medical staff and found that the most common risk for laser hair removal is burns and changes in pigmentation. Lesser common complications include increased sweating, rash, post-op pain.</p>\n\n<p>Benefits: From what I've read [See Reference], the main benefit is cosmetic satisfaction. Although the paper does mention the therapeutic effects against hirsutism/hypertrichosis (excessive hair growth). </p>\n\n<hr>\n\n<p>To address some of the other points you were mentioning: </p>\n\n<ol>\n<li><p>Removing hair does assist in odor control since hair is porous (readily absorbs odors). So less hair = less odor. </p></li>\n<li><p>Removing hair does not reduce sweating \"because the practice doesn't affect the glands that produce perspiration.\" Mayo Clinic explains \"These glands will continue to produce perspiration even when the hair is shaved down to skin level.\"</p></li>\n<li><p>For pubic hair removal, a study [See References] was done using a self-administered questionnaire (sample size 369 women) and the researchers found that \"The majority (60%) had experienced at least 1 health complication because of the removal, of which the most common were epidermal abrasion and ingrown hairs.\" Your mention of infection is certainly accounted for in the paper: \"This practice [pubic hair removal] may result in adverse health consequences, including genital burns from waxing, severe skin irritation leading to post inflammatory hyperpigmentation, vulvar and vaginal irritation and infection, and the spread or transmission of sexually transmitted infections (STI).\" From what I've seen, the research on adverse effects of pubic hair removal for men is less studied, but I did find a paper [See Reference] that mentions a positive correlation with STI's, but this conclusion is assuming that men are cutting themselves while shaving. </p></li>\n</ol>\n\n<hr>\n\n<p>References:</p>\n\n<p>Evidence-based review of hair removal using lasers and light\nsources:\n<a href=\"https://pdfs.semanticscholar.org/22e9/49a68c2731590e3e92afffa40e756e0bafee.pdf\" rel=\"nofollow noreferrer\">https://pdfs.semanticscholar.org/22e9/49a68c2731590e3e92afffa40e756e0bafee.pdf</a></p>\n\n<p>Adverse Effects of Laser Hair Removal: \n<a href=\"https://pdfs.semanticscholar.org/3bea/730adb6241154ec8dd08b901c18e61ecb90e.pdf\" rel=\"nofollow noreferrer\">https://pdfs.semanticscholar.org/3bea/730adb6241154ec8dd08b901c18e61ecb90e.pdf</a></p>\n\n<p>Sweating and Body Odor: \n<a href=\"https://health.howstuffworks.com/skin-care/underarm-care/tips/does-shaving-armpits-reduce-sweating.htm\" rel=\"nofollow noreferrer\">https://health.howstuffworks.com/skin-care/underarm-care/tips/does-shaving-armpits-reduce-sweating.htm</a></p>\n\n<p>Pubic Hair Removal Complications in Women Study: <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/24486227\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pubmed/24486227</a></p>\n\n<p>Pubic Hair Removal in Males, Trends:\n<a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5675231/\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5675231/</a></p>\n\n<hr>\n\n<p>Cheers. </p>\n", "score": 2 }, { "answer_id": 15092, "body": "<p>Most of the questions — especially about the benefits — are <a href=\"https://en.wikipedia.org/wiki/Hair_removal\" rel=\"nofollow noreferrer\">answered exhaustively on the Wikipedia page</a>. For medical reasons, in particular, the article states that</p>\n\n<blockquote>\n <p>In extreme situations people may need to remove all body hair to prevent or combat infestation by lice, fleas and other parasites.</p>\n</blockquote>\n\n<p>That said, the main <em>purpose</em> of hair removal is definitely aesthetic.</p>\n\n<p>Interesting, cultural pubic hair removal has had an unexpected positive side-effect: it has probably contributed substantially to the near-eradication of the <a href=\"https://en.wikipedia.org/wiki/Crab_louse\" rel=\"nofollow noreferrer\">pubic lice</a> (“crabs”), <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/24825336\" rel=\"nofollow noreferrer\">as reported</a>.</p>\n", "score": 0 } ]
8,688
CC BY-SA 4.0
Any benefits (or harms) for hair removal (beyond possible aesthetic reasons)?
[ "dermatology", "risks", "hygiene", "benefits", "laser-hair-removal" ]
<p>I hear a lot about hair removal (anything and everything) and its possible benefits, particularly in terms of sweating and odor control. However, I also hear people suggesting that hair removal (particularly in the pubis region) might increase the risk of skin infection.</p> <p>I have the impression that these claims were often mainly driven by people's aesthetic view regarding body hair and nobody could show me scientific evidence for their claims.</p> <p>Is there any scientific evidence suggesting <strong>benefits</strong> and <strong>risks</strong> of hair removal procedure?</p>
9
https://medicalsciences.stackexchange.com/questions/9067/washing-hands-after-going-to-the-washroom-to-prevent-epidemy
[ { "answer_id": 9102, "body": "<p>Hands play a major role especially in the transmission of blood-borne, fecal, and respiratory tract viruses. </p>\n\n<p><strong>Hand washing after use of bathroom aims at preventing the transmission of pathogens, which rely on faecal-oral transmission</strong>, such as rotavirus, noroviruses, enteroviruses in some cases hepatitis A virus (1). It prevents those pathogens from reaching the kitchen for example where it could lead to subsequent ingestion.</p>\n\n<p>Recently a systematic review (2) identified a total of 2881 unique publications addressing this question.</p>\n\n<p>Interestingly, this study found a varying prevalence of hand-washing after contact with extcreta:</p>\n\n<blockquote>\n <p>We estimate that 19% of people worldwide wash their hands with soap\n after contact with excreta. The regional mean prevalence of\n handwashing with soap ranges between 13% and 17% in low- and\n middle-income regions, and between 42% and 49% in high-income regions</p>\n</blockquote>\n\n<p><strong>However, the authors reported a 40% reduction in the risk of diarrhoea from the promotion of handwashing with soap (RR 0.60, 95% CI 0.53–0.68) suggesting that hand-washing impact on faecal oral transmission and reduces risk of diarrhoea.</strong></p>\n\n<p><em>Sources:</em></p>\n\n<ol>\n<li><p>Kampf G, Kramer A. Epidemiologic Background of Hand Hygiene and Evaluation of the Most Important Agents for Scrubs and Rubs. Clinical Microbiology Reviews. 2004;17(4):863-893.</p></li>\n<li><p>Freeman et al. Systematic review: Hygiene and health: systematic review of handwashing practices worldwide and update of health effects. Tropical Medicine and international health. Volume 19, Issue 8. August 2014. Pages 906–916 </p></li>\n</ol>\n", "score": 9 } ]
9,067
CC BY-SA 3.0
Washing hands after going to the washroom to prevent epidemy
[ "disease-transmission", "hygiene", "hand", "epidemiology", "public-sanitation" ]
<p>There is widespread agreement that one should wash its hands after going to the washroom. However, a large fraction of the population does not wash their hands. These types of signs became fairly common</p> <p><a href="https://i.stack.imgur.com/RvbL6m.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/RvbL6m.png" alt="enter image description here"></a> <a href="https://i.stack.imgur.com/DdnmUm.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/DdnmUm.jpg" alt="enter image description here"></a></p> <p><a href="https://i.stack.imgur.com/bVatAm.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/bVatAm.png" alt="enter image description here"></a></p> <p>I understand that lots of pathogens transmit through hands, whether it is through hand shacking or door knobs. However, <strong>it is unclear to me whether our hands carry significantly more pathogens after going to the washroom than before that</strong>.</p> <p>Is the advice <code>Wash you hands after going to the washroom</code> useful because...</p> <ul> <li>our hands are filthier after going to the washroom?</li> <li>it is just a good way for someone to not forget to wash its hands 5-8 times a day?</li> </ul>
9
https://medicalsciences.stackexchange.com/questions/9117/is-the-blue-light-emitted-by-computer-monitors-deleterious-for-the-human-eyes
[ { "answer_id": 19257, "body": "<blockquote>\n <p>Is the blue light emitted by computer monitors deleterious for the human eyes?</p>\n</blockquote>\n\n<p>No.</p>\n\n<p>UV from the Sun (or other strong UV sources, such as <a href=\"https://en.wikipedia.org/wiki/Germicidal_lamp#Safety_concerns\" rel=\"nofollow noreferrer\">germicidal bulbs</a>) is harmful.</p>\n\n<p>Blue light from a computer monitor or cellphone contains insufficient ultraviolet light to <strong>harm</strong> the eyes, the problem is that blue light causes the suppression of <a href=\"https://en.wikipedia.org/wiki/Melatonin#Sleep_disorders\" rel=\"nofollow noreferrer\">melatonin</a> which affects the onset of sleep, and close up viewing and concentration on digital devices reduces the blink rate by half to one third.</p>\n\n<p>The Canadian Association of Ophthalmology is more cautious in their warnings than their American counterpart, but the difference in the recommendation is that most people over 20 years old should be able to tolerate some blue light that isn't towards the UV end of the spectrum.</p>\n\n<p><strong>References</strong>:</p>\n\n<p>Canadian Association of Ophthalmology - \"<a href=\"https://opto.ca/health-library/blue-light-is-there-risk-of-harm\" rel=\"nofollow noreferrer\">Blue light - Is there a risk of harm?</a>\"</p>\n\n<p>UK Association of Opthalmologists - \"<a href=\"https://www.aop.org.uk/advice-and-support/policy/position-statements/visible-blue-light\" rel=\"nofollow noreferrer\">Our position on the clinical evidence and advice relating to visible blue light</a>\"</p>\n\n<p>American Academy of Ophthalmology - \"<a href=\"https://www.aao.org/eye-health/tips-prevention/should-you-be-worried-about-blue-light\" rel=\"nofollow noreferrer\">Should You Be Worried About Blue Light?</a>\"</p>\n\n<p>American Academy of Ophthalmology - \"<a href=\"https://www.aao.org/eye-health/tips-prevention/should-you-use-night-mode-to-reduce-blue-light\" rel=\"nofollow noreferrer\">Should You Use Night Mode to Reduce Blue Light?</a>\"</p>\n\n<p>American Academy of Ophthalmology - \"<a href=\"https://www.aao.org/eye-health/tips-prevention/computer-usage\" rel=\"nofollow noreferrer\">Computers, Digital Devices and Eye Strain</a>\"</p>\n\n<p>PubSci - \"<a href=\"https://www.ncbi.nlm.nih.gov/pubmed/25535358\" rel=\"nofollow noreferrer\">Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness</a>\" (Jan 27 2015), by AM Chang, D Aeschbach, JF Duffy, and CA Czeisler.</p>\n\n<p><strong>Disclaimer</strong>: Neither Stack Exchange nor the author offer medical advice.</p>\n\n<p>Some websites offer a stronger viewpoint, opposing blue light.</p>\n\n<p>PreventBlindness.org's <a href=\"https://www.preventblindness.org/prevent-blindness-board-directors\" rel=\"nofollow noreferrer\">About Page</a> discloses that some of the Board of Directors work for eyewear companies, they offer this advice: \"<a href=\"https://www.preventblindness.org/blue-light-and-your-eyes\" rel=\"nofollow noreferrer\">Blue light and your eyes</a>\" while the website BlueLightExposed.com has <strong>no About webpage</strong> and offers this advice: \"<a href=\"http://www.bluelightexposed.com/#blue-light-and-digital-eyestrain\" rel=\"nofollow noreferrer\">Blue light and macular degeneration</a>\".</p>\n\n<p>Wikipedia's webpage on <a href=\"https://en.wikipedia.org/wiki/High-energy_visible_light\" rel=\"nofollow noreferrer\">High Energy Visible Light</a> is inconclusive for adults.</p>\n\n<p>There are more unbiased \"no\" sources than \"yes\" sources. Blink and take breaks.</p>\n", "score": 3 } ]
9,117
CC BY-SA 3.0
Is the blue light emitted by computer monitors deleterious for the human eyes?
[ "computers", "ophthalmology", "irreversible-damage", "eye-strain" ]
<p>Is the blue light emitted by computer monitors deleterious for the human eyes? By deleterious, I mean irreversible damage.</p> <p>I read some conflicting information:</p> <p><a href="http://www.drweil.com/health-wellness/body-mind-spirit/vision/do-orange-glasses-block-blue-light/" rel="noreferrer">http://www.drweil.com/health-wellness/body-mind-spirit/vision/do-orange-glasses-block-blue-light/</a></p> <blockquote> <p>Blue light isn’t harmful during daylight hours – in fact, it enhances attention, reaction times, and mood).</p> </blockquote> <p><a href="http://www.gunnars.com/how-they-work/" rel="noreferrer">http://www.gunnars.com/how-they-work/</a> :</p> <blockquote> <p>Cumulative exposure to artificial blue-light can contribute to vision problems such as cataracts and age-related macular degeneration [...] The Vision Council: Nearly 70% of American adults experience some form of digital eye strain due to prolonged use of electronic devices.</p> </blockquote> <p>I noticed that some pro-gamers wear orange glasses:</p> <p><a href="https://i.stack.imgur.com/UxIzA.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/UxIzA.jpg" alt="enter image description here"></a></p>
9
https://medicalsciences.stackexchange.com/questions/10013/how-to-remove-the-yellow-stains-from-my-teeth
[ { "answer_id": 12125, "body": "<p>There are a few aspects that need to be addressed.</p>\n\n<p>1) <strong>Diet &amp; Oral habits</strong>: Often, drinks with natural or artificial coloring will stain the surface of the enamel and any tartar (calcified plaque) that rests on your tooth. Some oral products (ex: smoking) and medication (ex: some mouthrinces and some antibiotics) are also known to cause discoloration. Any long-term solutions will require you to examine the cause of the coloration, and whether there are underlying causes for it (a more in-depth look at teeth coloration can be fond here: <a href=\"http://www.nature.com/bdj/journal/v190/n6/full/4800959a.html\" rel=\"nofollow noreferrer\">1</a>).</p>\n\n<p>2) <strong>Cleaning and scaling</strong>: A dental health professional can remove the tartar and remove external coloration. This procedure has to be performed every 6-12 months if not more often, depending on that professional's assessment of your current health <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4555792/\" rel=\"nofollow noreferrer\">2</a>.</p>\n\n<p>3) <strong>Chemical treatment</strong> If all external coloration has been removed, and you are still dissatisfied with your tooth color, a dentist can assess and prescribe you a whitening agent, or otherwise recommend an off the shelf solution but this is beyond the scope of the original question.</p>\n\n<p>Sources:</p>\n\n<ol>\n<li><a href=\"http://www.nature.com/bdj/journal/v190/n6/full/4800959a.html\" rel=\"nofollow noreferrer\">http://www.nature.com/bdj/journal/v190/n6/full/4800959a.html</a></li>\n<li><a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4555792/\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4555792/</a></li>\n</ol>\n", "score": 3 } ]
10,013
CC BY-SA 3.0
How to remove the yellow stains from my teeth?
[ "dentistry", "coloration-discoloration", "removal", "brushing-teeth", "bleach-teeth-whitening" ]
<p>How to remove the yellow stains from my teeth?</p> <p>I brush two times a day once in the morning and once in the night.But I am still having yellow stains in my teeth.The back side of two of my teeth have also turned brown.</p> <p>I have also brushed with baking powder for 3-4 days but no result came .</p> <p>What should I do to get natural color of my teeth back?Please help.</p>
9
https://medicalsciences.stackexchange.com/questions/11268/dealing-with-triangle-puncture-wounds
[ { "answer_id": 18692, "body": "<p>A triangular wound can possibly be sutured, depending on many considerations regarding the wound including its type, condition, location, size, shape, depth, cleanliness vs presence of debris, mechanism of injury, the force of the injury, the age of the wound, tension on the wound, the patient’s medical history, species if the wound is a bite, etc... </p>\n\n<p>In “stellate” wounds, tissue viability is a major consideration before proceeding. (Wound preparation is an extensive topic not covered here.) The triangular bits at the center of the wound are at risk of not being viable (or savable) tissue if there is inadequate circulation to that specific area. If the triangular tips are pink and the subcutaneous tissue appears to be intact and adequately supportive, then a “purse-string” suture can be considered for bringing those points together, followed by placement of ordinary straight suturing of the “arms” of the stellate wound.\n<a href=\"https://i.stack.imgur.com/Oot8l.jpg\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/Oot8l.jpg\" alt=\"stellate wound with purse string suture\"></a><a href=\"https://www.slideshare.net/cruzasma/woundcare\" rel=\"nofollow noreferrer\">(The above image is from this wound care slideshow at slideshare.net)</a></p>\n\n<p><a href=\"https://i.stack.imgur.com/JOQje.jpg\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/JOQje.jpg\" alt=\"my drawing of a purse-string closed wound with suturing completed\"></a>(My drawing of a purse-string-closed wound with further suturing of the branches of the wound completed.)</p>\n\n<p>If the triangular tips are pale, grey or purple, or have no obvious subcutaneous support, they would be deemed non-viable and would therefore be removed from the wound, thus requiring a larger excisional solution. One possibility would be to cut an elliptical excision around the entire wound, which would then be closed by pulling the edges together with simple interrupted sutures. (This is similar to the excisional method used for biopsies or removal of cancerous cutaneal lesions.) \n<a href=\"https://i.stack.imgur.com/wBajw.jpg\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/wBajw.jpg\" alt=\"my drawing of an elliptical excision and suturing\"></a> (My drawing of an elliptical excision and suturing.)</p>\n\n<p>Of course this entire explanation is a gross oversimplification of a process which actually requires extensive professional training. My reference for the above material is <a href=\"https://www.slideshare.net/cruzasma/woundcare\" rel=\"nofollow noreferrer\">this excellent slide show summarizing the entire suturing process</a>, paraphrased through the lens of my own experience.</p>\n", "score": 4 }, { "answer_id": 15218, "body": "<p>Triangular blades were created for pretty much one reason, and one reason only. The triangular cross section made a stronger blade, ensuring more damage was done in a charge/stab versus a flat blade.</p>\n\n<p>The triangular blade was introduced in the early 1700's, mostly due to strength reasons. A triangular blade is less likely to bend/break when stabbing in a charge, especially if you hit a piece of armor, another weapon or bone. The cross section is much stronger in a triangle versus a flat blade.</p>\n\n<p>There is anecdotal evidence galore about the wound, and <a href=\"https://en.wikipedia.org/wiki/Bayonet\" rel=\"nofollow noreferrer\">the wiki states</a> that it is harder to heal, as the scar tissue filling in the wound tends to pull apart the rest of the wound as it heals. I can find several anecdotal references, but nothing concrete to confirm this. There is also anecdotal evidence that the Geneva Convention bans triangular blades, however the language only states \"weapons that cause unneeded suffering\" (paraphrased). </p>\n\n<p>Pretty much the only reason for them was strength, and as other weapons became better, the bayonet went back to a single/double blade, as they are much more useful in that shape in non combat situations (Cutting ropes, food, straps, etc).</p>\n", "score": 3 } ]
11,268
CC BY-SA 3.0
Dealing with triangle puncture wounds
[ "wound-care", "bleeding", "stitches", "penetrate-trauma-wound", "knife-stab-wound" ]
<p><a href="https://i.stack.imgur.com/dtoii.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/dtoii.jpg" alt="enter image description here"></a></p> <p>In that picture it mentions how triangle wounds are impossible to stitch up. If that is true how would one treat a triangle puncture wound on the human body?</p>
9
https://medicalsciences.stackexchange.com/questions/13573/does-cinnamon-accelerate-metabolism
[ { "answer_id": 13675, "body": "<p>Despite being a long known spice and its known <a href=\"https://en.wikipedia.org/wiki/Cinnamon#Traditional_medicine\" rel=\"nofollow noreferrer\">role in traditional medicine</a> the modern evidence for health related benefits and detriments of cinnamon are sparse.The NCCIH sums it up with <a href=\"https://nccih.nih.gov/health/cinnamon\" rel=\"nofollow noreferrer\">NCCIH Publication No.463: Cinnamon</a>: </p>\n\n<blockquote>\n <p>Studies done in people don’t support using cinnamon for any health\n condition.</p>\n</blockquote>\n\n<p>Cinnamon is indeed used in the way the OP phrased it, but whether it is really effective remains currently dubious.</p>\n\n<h1>Results in Favour of Cinnamon</h1>\n\n<p>There are some scientific studies showing very interesting and promising results like:</p>\n\n<p><a href=\"https://www.hindawi.com/journals/ppar/2008/581348/abs/\" rel=\"nofollow noreferrer\">Improved Insulin Resistance and Lipid Metabolism by Cinnamon Extract through Activation of Peroxisome Proliferator-Activated Receptors</a></p>\n\n<blockquote>\n <p>Peroxisome proliferator-activated receptors (PPARs) are\n transcriptional factors involved in the regulation of insulin\n resistance and adipogenesis. Cinnamon, a widely used spice in food\n preparation and traditional antidiabetic remedy, is found to activate\n PPAR and , resulting in improved insulin resistance, reduced fasted\n glucose, FFA, LDL-c, and AST levels in high-caloric diet-induced\n obesity (DIO) and mice in its water extract form. In vitro studies\n demonstrate that cinnamon increases the expression of peroxisome\n proliferator-activated receptors and (PPAR/) and their target genes\n such as LPL, CD36, GLUT4, and ACO in 3T3-L1 adipocyte. The\n transactivities of both full length and ligand-binding domain (LBD) of\n PPAR and PPAR are activated by cinnamon as evidenced by reporter gene\n assays. These data suggest that cinnamon in its water extract form can\n act as a dual activator of PPAR and , and may be an alternative to\n PPAR activator in managing obesity-related diabetes and\n hyperlipidemia.</p>\n</blockquote>\n\n<p><a href=\"http://www.sciencedirect.com/science/article/pii/S089990071200144X\" rel=\"nofollow noreferrer\">Cinnamon polyphenols regulate multiple metabolic pathways involved in insulin signaling and intestinal lipoprotein metabolism of small intestinal enterocytes</a></p>\n\n<blockquote>\n <p><strong>Results</strong> \n Ex vivo, the cinnamon extract significantly decreased the amount of\n apolipoprotein-B48 secretion into the media, inhibited the mRNA\n expression of genes of the inflammatory cytokines, interleukin-1β,\n interleukin-6, and tumor necrosis factor-α, and induced the expression\n of the anti-inflammatory gene, Zfp36. CE also increased the mRNA\n expression of genes leading to increased insulin sensitivity,\n including Ir, Irs1, Irs2, Pi3k, and Akt1, and decreased Pten\n expression. CE also inhibited genes associated with increased\n cholesterol, triacylglycerols, and apolipoprotein-B48 levels,\n including Abcg5, Npc1l1, Cd36, Mttp, and Srebp1c, and facilitated\n Abca1 expression. CE also stimulated the phospho-p38 mitogen-activated\n protein kinase, c-Jun N-terminal kinase, and\n extracellular-signal-regulated kinase expressions determined by flow\n cytometry, with no changes in protein levels. </p>\n \n <p><strong>Conclusions</strong>\n These results demonstrate that the CE regulates genes associated with\n insulin sensitivity, inflammation, and cholesterol/lipogenesis\n metabolism and the activity of the mitogen-activated protein kinase\n signal pathway in intestinal lipoprotein metabolism.</p>\n</blockquote>\n\n<p><a href=\"http://journals.sagepub.com/doi/abs/10.1177/193229681000400324\" rel=\"nofollow noreferrer\">Cinnamon: Potential Role in the Prevention of Insulin Resistance, Metabolic Syndrome, and Type 2 Diabetes</a></p>\n\n<blockquote>\n <p>Metabolic syndrome is associated with insulin resistance, elevated\n glucose and lipids, inflammation, decreased antioxidant activity,\n increased weight gain, and increased glycation of proteins. Cinnamon\n has been shown to improve all of these variables in <em>in vitro</em>, animal,\n and/or human studies. In addition, cinnamon has been shown to\n alleviate factors associated with Alzheimer's disease by blocking and\n reversing tau formation <em>in vitro</em> and in ischemic stroke by blocking\n cell swelling. <em>In vitro</em> studies also show that components of cinnamon\n control angiogenesis associated with the proliferation of cancer\n cells. Human studies involving control subjects and subjects with\n metabolic syndrome, type 2 diabetes mellitus, and polycystic ovary\n syndrome all show beneficial effects of whole cinnamon and/or aqueous\n extracts of cinnamon on glucose, insulin, insulin sensitivity, lipids,\n antioxidant status, blood pressure, lean body mass, and gastric\n emptying. However, not all studies have shown positive effects of\n cinnamon, and type and amount of cinnamon, as well as the type of\n subjects and drugs subjects are taking, are likely to affect the\n response to cinnamon. In summary, components of cinnamon may be\n important in the alleviation and prevention of the signs and symptoms\n of metabolic syndrome, type 2 diabetes, and cardiovascular and related\n diseases.</p>\n</blockquote>\n\n<h3>Metabolism Accelerator?</h3>\n\n<p>The most promising indicators going into the direction of the question's \"metabolism acceleration\" might be found in studies like these:</p>\n\n<p><a href=\"https://linkinghub.elsevier.com/retrieve/pii/S0026-0495(17)30212-3\" rel=\"nofollow noreferrer\">Cinnamaldehyde induces fat cell-autonomous thermogenesis and metabolic reprogramming:</a></p>\n\n<blockquote>\n <p>CA activates thermogenic and metabolic responses <strong>in mouse and human primary subcutaneous adipocytes</strong> in a cell-autonomous manner, giving a mechanistic explanation for the anti-obesity effects of CA observed previously and further supporting its <strong>potential metabolic benefits on humans</strong>. Given the wide usage of cinnamon in the food industry, the notion that this popular food additive, instead of a drug, may activate thermogenesis, could ultimately lead to therapeutic strategies against obesity that are much better adhered to by participants.</p>\n</blockquote>\n\n<h1>Inconclusive Results</h1>\n\n<p>But trying to gain a systematic view on such a complex substance is quite a challenge.\nThe Cochrane Library concludes in <a href=\"http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD007170.pub2/full\" rel=\"nofollow noreferrer\">Cinnamon for diabetes mellitus</a>:</p>\n\n<blockquote>\n <p>There is insufficient evidence to support the use of cinnamon for type\n 1 or type 2 diabetes mellitus. Further trials, which address the\n issues of allocation concealment and blinding, are now required. The\n inclusion of other important endpoints, such as health-related quality\n of life, diabetes complications and costs, is also needed.</p>\n</blockquote>\n\n<p>Another 2011 Research Summary:</p>\n\n<blockquote>\n <p>One fairly well-studied supplement used to help hyperglycemia in diabetics is cassia cinnamon. Animal and laboratory studies have indicated that cinnamon may mimic the effects of insulin and make cells more sensitive to insulin (Anderson et al., 2004).\n In diabetic patients, some studies have shown a favorable response; some no effect. The most comprehensive review of cinnamon use in diabetics, published in 2008 by the journal Diabetes Care (Baker et al., 2008), found no metabolic benefits to the use of cinnamon by type I or type II diabetics. Specifically, no benefits to fasting blood glucose, lipids, or cholesterol were observed in a meta-analysis of five small clinical trials.<a href=\"http://Ronald%20Ross%20Watson%20and%20Victor%20R.%20Preedy:\" rel=\"nofollow noreferrer\" title=\"Bioactive Food As Dietary Interventions For Diabetes\"> [Ronald Ross Watson and Victor R. Preedy: \"Bioactive Food As Dietary Interventions For Diabetes\", Academic Press: San Diego, London, 2013</a>, p377.]</p>\n</blockquote>\n\n<p>Whereas an article in Annals of Family Medicine sees it in more positive light:</p>\n\n<p><a href=\"https://www.ncbi.nlm.nih.gov/pubmed/24019277\" rel=\"nofollow noreferrer\">Cinnamon use in type 2 diabetes: an updated systematic review and meta-analysis.</a></p>\n\n<blockquote>\n <p>The consumption of cinnamon is associated with a statistically\n significant decrease in levels of fasting plasma glucose, total\n cholesterol, LDL-C, and triglyceride levels, and an increase in HDL-C\n levels; however, no significant effect on hemoglobin A1c was found.\n The high degree of heterogeneity may limit the ability to apply these\n results to patient care, because the preferred dose and duration of\n therapy are unclear.</p>\n</blockquote>\n\n<h1>Summary</h1>\n\n<p>Please note that most of the positive results where obtained in beakers and rats, while studies of its effect in humans are mostly either negative, not replicated or inconclusive. Citing a single study that is not a fundamental and large breakthrough is usually a good indication that the newspapers have filled their bogus pipeline.</p>\n\n<p>The effect on metabolic rate seems to be out of focus for the interest in cinnamon and its most promising fields of application as a medicine are directed to diabetes and metabolic syndrome. Whether those sources cited by the OP have <em>any</em> background in valid and reliable scientific evidence seems unlikely. More likely is that they are all examples of 'journalism' (this is meant as an insult) and bad science communication: Taking preliminary findings and blowing them out of proportion, misrepresenting the facts given to them.</p>\n\n<p>Cinnamon in moderation as a spice is nice. If used as an agreeable herb that makes fibrous ingredients more attractive without adding much calories it is superb. If taken as a medicine or supplement it can be quite ineffective and at the same time dangerous. This is especially true if one does not differentiate between cinnamon and cassia. If using large amounts of cinnamon might still be a goal then there are some more things to consider:</p>\n\n<p><a href=\"https://health.stackexchange.com/q/508/11231\">How much cinnamon is too much?</a></p>\n", "score": 5 } ]
13,573
CC BY-SA 3.0
Does cinnamon accelerate metabolism?
[ "nutrition", "metabolism", "cinnamon" ]
<p>In the past couple of days, I've repeatedly heard and read that cinnamon consumption increases the metabolic rate in humans. A <a href="https://www.google.de/search?rls=en&amp;q=does%20cinnamon%20accelerate%20metabolism" rel="nofollow noreferrer">Google search</a> brings up plenty of results.</p> <p>However, few of them cite any concrete evidence. In fact, even those that mention sources point to circumstantial evidence at best. For instance <a href="http://www.livestrong.com/article/491512-does-cinnamon-increase-metabolism/" rel="nofollow noreferrer">Livestrong.com</a> states</p> <blockquote> <p>A 2012 study published in the International Journal of Preventative Medicine investigated the effects of cinnamon in people with type 2 diabetes. One group took cinnamon supplements every day, while the other group took a placebo. After eight weeks, the cinnamon group lost more weight and body fat than the group taking the placebo, even though the cinnamon group did not make any changes to their usual eating habits.</p> </blockquote> <p>Similarly, all <a href="http://www.12minuteathlete.com/10-hacks-boost-metabolism/" rel="nofollow noreferrer">12minuteathlete.com</a> put forth to back their claim is</p> <blockquote> <p>If you’ve ever read the 4-Hour Body by Tim Ferris (and if you haven’t, I highly recommend it), you probably remember the section on his cinnamon experiments. Basically, he found that eating about one and a half teaspoons of cinnamon a day can help regulate glucose levels, which in turn helps control weight gain.</p> </blockquote> <p><a href="http://idealbite.com/cinnamon-for-weight-loss/" rel="nofollow noreferrer">Idealbite.com</a> goes into more detail about the purported effects of cinnamon on the body and mentions two studies but doesn't give links or any information with which to find either of them.</p> <p>So basically, my question is how much evidence is there really for the metabolism-accelerating effects of cinnamon intake and how conclusive is it?</p>
9
https://medicalsciences.stackexchange.com/questions/14808/which-one-is-more-harmful-for-your-kidneys-drinking-more-or-less-water
[ { "answer_id": 14813, "body": "<p><strong>Background reading</strong></p>\n\n<p>Even though your fluid intake can be highly variable, the total volume of fluid in your body normally remains stable. Homeostasis of body fluid volume depends in large part on the ability of the kidneys to regulate the rate of water loss in urine.</p>\n\n<p>Normally functioning kidneys produce a large volume of dilute urine when fluid intake is high, and a small volume of concentrated urine when fluid intake is low or fluid loss is large. The Anti Diuretic Hormone (<strong>ADH</strong>)/sometimes called <strong>arginine vasopressin</strong> controls whether dilute urine or concentrated urine is formed. In the absence of ADH, urine is very dilute. However, a high level of ADH stimulates reabsorption of more water into blood, producing a concentrated urine.</p>\n\n<blockquote>\n <p>When water intake is low or water loss is high (such as during heavy\n sweating), the kidneys must conserve water while still eliminating\n wastes and excess ions. Under the influence of ADH, the kidneys\n produce a small volume of highly concentrated urine. Urine can be four\n times more concentrated (up to 1200 mOsm/liter) than blood plasma or\n glomerular filtrate (300 mOsm/liter). The kidney is crucial in\n regulating water balance and blood pressure as well as removing waste\n from the body. Water metabolism by the kidney can be classified into\n regulated and obligate. Water regulation is hormonally mediated, with\n the goal of maintaining a tight range of plasma osmolality between 275\n to 290 mOsm/kg.</p>\n</blockquote>\n\n<hr>\n\n<p><strong>Substianting the answer</strong></p>\n\n<blockquote>\n <p>In addition to regulating fluid balance, the kidneys require water for\n the filtration of waste from the blood stream and excretion via urine.\n Water excretion via the kidney removes solutes from the blood, and a\n minimum obligate urine volume is required to remove the solute load\n with a maximum output volume of 1 L/h. </p>\n</blockquote>\n\n<p></p>\n\n<blockquote>\n <p>The kidneys <strong>function more efficiently in the presence of an abundant\n water supply</strong>. If the kidneys economize on water, producing a more\n concentrated urine, <strong>there is a greater cost in energy and more wear on\n their tissues</strong>. This is especially likely to occur when the kidneys are\n under stress, for example when the diet contains excessive amounts of\n <strong>salt or toxic substances that need to be eliminated. Consequently,\n drinking enough water helps protect this vital organ</strong>. In cases of\n water loading, if the volume of water ingested cannot be compensated\n for with urine output, having overloaded the kidney’s maximal output\n rate an individual can enter a hyponatremic state</p>\n</blockquote>\n\n<hr>\n\n<p><strong>Concluding remarks</strong></p>\n\n<p><em>Note: Is it very important to understand that both dehydration or overhydration both pose equally disastrous effects on health. While the former is associated with orthostatic hypotension, delirium and morbidities the latter has been reported to be associated with water intoxication and hyponatremia, proteinuria etc.</em></p>\n\n<hr>\n\n<p><strong>References</strong></p>\n\n<ol>\n<li>Water, Hydration and Health. Barry M. Popkin, Kristen E. D’Anci, and Irwin H. Rosenberg. Nutr Rev. 2010 Aug; 68(8): 439–458.doi: <a href=\"https://dx.doi.org/10.1111%2Fj.1753-4887.2010.00304.x\" rel=\"noreferrer\">10.1111/j.1753-4887.2010.00304.x.</a></li>\n<li>Principles of Anatomy and Phisiology G. Tortora: Urinary system</li>\n<li>Excessive fluid intake as a novel cause of proteinuria. F Clark et al. Available at: <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2175005/\" rel=\"noreferrer\">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2175005/</a></li>\n</ol>\n", "score": 6 } ]
14,808
CC BY-SA 3.0
Which one is more harmful for your kidneys, drinking more or less water?
[ "water", "kidney" ]
<p>Which is more harmful for your kidneys? Drinking more than enough water or having less than the minimum amount required?</p>
9
https://medicalsciences.stackexchange.com/questions/15277/is-it-beneficial-to-keep-using-fluorised-toothpaste-after-prolonged-use
[ { "answer_id": 15279, "body": "<p>Fluoride can be absorbed into the teeth and form fluoroapatite only in children up to 6-8 years of age (<a href=\"https://www.webmd.com/oral-health/guide/fluoride-treatment\" rel=\"noreferrer\">WebMD</a>). </p>\n\n<p>Later, fluoride from toothpaste may still be helpful, because it stimulates the incorporation of calcium and phosphorus into the enamel that has been demineralized (<a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1543617/\" rel=\"noreferrer\">PubMed Central, 2006</a>). So, fluoride stimulates remineralization and thus <em>slows down</em> the development of caries; it doesn't mean that it <em>cures</em> caries.</p>\n\n<p><a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4606595/\" rel=\"noreferrer\">Recent advancements in fluoride: A systematic review (PubMed Central, 2015)</a></p>\n\n<blockquote>\n <p>A summary of RCTs on fluoride concentration in toothpastes showed a\n positive dose response: Pastes with 1000–1500 ppm F showed 23% caries\n reduction compared to fluoride-free placebo; this value increased to\n 36% for pastes with around 2500 ppm F. For pastes having below 1000\n ppm F, no significant difference was found with placebo, probably due\n to the small number of studies.</p>\n</blockquote>\n\n<p>^^ The above means, there was less caries after fluoridated paste use, and not that the established caries was cured. </p>\n", "score": 11 }, { "answer_id": 15617, "body": "<p>The main protective effect of fluoride is outside the tooth, not inside. </p>\n\n<blockquote>\n <p>Small amounts of fluoride in solution around the tooth inhibit\n demineralization more effectively than incorporated fluoride and have\n a much greater caries-protective potential than a large proportion of\n fluorapatite in enamel mineral. Schweiz Monatsschr Zahnmed 122:\n 1030–1036 (2012)</p>\n</blockquote>\n\n<p>For example, even an incredible amount of fluoride has limited protective effect. In a <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/2839893\" rel=\"nofollow noreferrer\">classic study</a>, Ogaard compared the resistance of fluoroapatite (shark enamel) and hydroxyapatite (human enamel) against a high caries challenge in a human in vivo model. Two samples of shark enamel and human enamel were each placed in removable appliances in six children and carried for 1 month and a plaque retentive device was placed over each enamel sample. The results showed that the mean total mineral loss (delta Z) was 1680 vol% micron in human enamel and 965 vol% micron in shark enamel. The corresponding mean values for lesion depth were 90 micron and 36 micron, respectively. It was concluded that <strong>even shark enamel containing 30,000 ppm F has a limited resistance against caries attacks</strong>.</p>\n\n<p>In a later <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/11908400\" rel=\"nofollow noreferrer\">review</a>, the same author concludes that </p>\n\n<blockquote>\n <p>The fluoride concentration in the apatitic structure of enamel does\n not have as significant an effect on reducing caries as a continuous\n presence of fluoride in the plaque liquid.</p>\n</blockquote>\n\n<p>Hence, to receive the protective effect of the fluoride, we require to keep it near the tooth surface all time. </p>\n", "score": 5 } ]
15,277
CC BY-SA 3.0
Is it beneficial to keep using fluorised toothpaste after prolonged use?
[ "dentistry", "risks", "brushing-teeth", "biochemistry", "fluoride" ]
<p>As far as I understand, fluoride helps in hardening the enamel of our teeth by replacing the calcium element in hydroxyapatite to convert it in the stronger fluorapatite, like explained <a href="https://biology.stackexchange.com/questions/19032/how-is-the-fluoride-in-toothpaste-absorbed">here</a>. Wether that's worth other potential risks of using fluor is debatable, but let's keep that aside. I'm curious if it is still beneficial to keep using fluorised toothpaste if you already did so for like 10 years. I suppose all hydroxyapatite is long converted into fluorapatite already after so much brushing. Why would it still be recommendable to keep using it?</p>
9
https://medicalsciences.stackexchange.com/questions/16586/general-population-low-vitamin-d-levels
[ { "answer_id": 16588, "body": "<p>There are a few mechanisms at work that influence the vitamin D status for Europeans. Vitamin D is either eaten in the food, <a href=\"http://ajcn.nutrition.org/content/61/3/638S.abstract\" rel=\"nofollow noreferrer\">created with the help of sunlight</a> or <a href=\"https://www.jwatch.org/jd201006040000002/2010/06/04/how-much-sunlight-equivalent-vitamin-d\" rel=\"nofollow noreferrer\">supplemented</a>. Many appear to net have enough it:</p>\n\n<blockquote>\n <p>Humans get vitamin D from exposure to sunlight, from their diet, and from dietary supplements. A diet high in oily fish prevents vitamin D deficiency. Solar ultraviolet B radiation (wavelength, 290 to 315 nm) penetrates the skin and converts 7-dehydrocholesterol to previtamin D3, which is rapidly converted to vitamin D3. Because any excess previtamin D3 or vitamin D3 is destroyed by sunlight, excessive exposure to sunlight does not cause vitamin D3 intoxication.\n Few foods naturally contain or are fortified with vitamin D. The “D” represents D2 or D3. Vitamin D2 is manufactured through the ultraviolet irradiation of ergosterol from yeast, and vitamin D3 through the ultraviolet irradiation of 7-dehydrocholesterol from lanolin. Both are used in over-the-counter vitamin D supplements, but the form available by prescription in the United States is vitamin D2.<br>\n <sub><a href=\"http://www.beauty-review.nl/wp-content/uploads/2015/04/Vitamin-D-deficiency.pdf\" rel=\"nofollow noreferrer\">Vitamin D deficiency, MF Holick - New England Journal of Medicine, 2007 - Mass Medical Soc</a></sub></p>\n</blockquote>\n\n<p>Since you are primarily interested in D-sunlight: </p>\n\n<p><a href=\"https://www.ncbi.nlm.nih.gov/pubmed/17237325?dopt=Abstract\" rel=\"nofollow noreferrer\">Pigmentation of the skin</a>: the amount of \"black\" people now living in Europe is rising. While that number is not significant for most cases often discussed, <em>all</em> of them (the more melanin the worse) have difficulty getting enough vitamin D from sunlight alone north of the 37th parallel.</p>\n\n<blockquote>\n <p><a href=\"https://i.stack.imgur.com/J31cb.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/J31cb.png\" alt=\"enter image description here\"></a><br>\n <sub><a href=\"https://www.health.harvard.edu/staying-healthy/time-for-more-vitamin-d\" rel=\"nofollow noreferrer\">From Harvard Women's Health Watch: Time for more vitamin D, 2008</a></sub></p>\n</blockquote>\n\n<p>Why the 35th, 37th or 40th parallel? Because the angle of the sun enables the atmosphere to filter out much of the UV rays needed to synthesise vitamin D. That angle is also varying during the day!</p>\n\n<p>The reference <a href=\"http://www.nice.org.uk/nicemedia/live/11871/49665/49665.pdf\" rel=\"nofollow noreferrer\">Cancer Research UK. (2010). Vitamin D expert review</a> already states clearly:</p>\n\n<blockquote>\n <p>The amount of UVB in sunlight changes substantially with season, latitude and time of day. These factors greatly affect vitamin D production, which is greatest around two hours either side of solar noon, and during summer months. </p>\n</blockquote>\n\n<p>Mad dogs and Englishmen go out in the midday sun? Many Europeans are around noon: in school, at work, in nursing homes -> indoors. Some cannot get out, others are not allowed to for different reasons.</p>\n\n<p>Those that do get out at the right time, in summer, around noon, are now scared into wearing hats and sunscreens for \"reasons\" (skin cancer, photoaging etc). The sun's rays have to reach the skin and penetrate it. For the right amount of time and with the right amount of intensity. The equation UVB equals bad leads to inadequate sun exposure and that to inadequate vitamin D synthesis. We have to choose our poison here and are currently opting for weaker bones (excuse the exaggeration).</p>\n\n<p>Some individuals in lower latitudes get enough sun for sure, and yet their vitamin D status is low:</p>\n\n<blockquote>\n <p><a href=\"https://academic.oup.com/jcem/article/92/6/2130/2597445/Low-Vitamin-D-Status-despite-Abundant-Sun-Exposure\" rel=\"nofollow noreferrer\">\"Low Vitamin D Status despite Abundant Sun Exposure\" N. Binkley et al., The Journal of Clinical Endocrinology &amp; Metabolism, Volume 92, Issue 6, 1 June 2007, Pages 2130–2135</a>, <a href=\"https://doi.org/10.1210/jc.2006-2250\" rel=\"nofollow noreferrer\">https://doi.org/10.1210/jc.2006-2250</a>\n A probable explanation for the “low” 25(OH)D status of some individuals is found in their failure to obtain high circulating D3 concentrations. Possible explanations for this include inadequate cutaneous production of D3, enhanced cutaneous destruction of previtamin D3 or vitamin D3, down-regulation of cutaneous synthesis by sun-induced melanin production, or abnormalities of transport from the skin to the circulation.</p>\n \n <p><sub>From Wolfgang Herrmann and Rima Obeid (Eds): \"Vitamins in the prevention of human diseases\", 2011, Walter de Gruyter, Berlin/New York:</sub><br>\n Cutaneously synthesized or orally ingested vitamin D is transported in the circulation bound to vitamin D binding protein (DBP). In the blood, only a small fraction is present as free, unbound vitamin D metabolites. The 25-hydroxylation of both vitamin D2 or vitamin D3, is the initial step in vitamin D activation. This takes place primarily in the liver. […] Nevertheless, extra-hepatic sources of 25-hydroxylation have been described in humans as well. They include macrophages, fibroblasts, keratinocytes and arterial endothelial cells (Gascon-Barre, 2005). (p. 365)</p>\n</blockquote>\n\n<p>And there comes another factor into play: a trend to low animal derived nutrition or even veganism. You may eat a lot of liver and obtain all the vitamin D you need, and more, from that. Eating offal is on the decline and plant based nutrition is usually very low in vitamin D. </p>\n\n<p>And low in cholesterol as well!</p>\n\n<blockquote>\n <p>There are no reports of vitamin D intoxication in healthy adults after intensive sunlight exposure. Vitamin D in the skin reaches a plateau after only 15–30 min of UVB exposure. Then, vitamin D-inactive substances such as lumisterol and tachysterol are produced, which do not reach the systemic circulation. (p. 367)\n That means that only a small amount is available:</p>\n \n <p><strong>Its precursor 7-dehydrocholesterol</strong> in the plasma membranes of both epidermal basal and suprabasal keratinocytes and dermal fibroblasts is converted to previtamin D3. Cutaneously synthesized vitamin D3 is released from the plasma membrane and enters the systemic circulation bound to vitamin D-binding protein (DBP) […] Factors influencing vitamin D levels Nutrient deficiencies are usually the result of dietary inadequacy, impaired absorption and use, increased requirement, or increased excretion. Vitamin D deficiency can occur when usual intake is lower than recommended levels over time, exposure to sunlight is limited, the kidneys cannot convert 25(OH)D to its active form, or absorption of vitamin D from the digestive tract is inadequate. Vitamin D-deficient diets are associated with milk allergy, lactose intolerance, ovo-vegetarianism, and veganism. Regarding the amount of vitamin D production in human skin, it depends on several variables including environmental factors such as geographic latitude, season, time of day, weather conditions (cloudiness), amount of air pollution and surface reflection which can all interfere with the amount of UVB radiation reaching the skin […] The skin is unique in being not only the source of vitamin D for the body but also in being capable of responding to the active metabolite of vitamin D, 1,25(OH)2D. Both 1,25(OH)2D and its receptor (VDR) play essential roles in the skin.<br>\n <sub>From: <a href=\"http://www.sciencedirect.com/science/article/pii/S209012321400023X\" rel=\"nofollow noreferrer\">Vitamin D and the skin: Focus on a complex relationship: A review</a> 2015.</sub> </p>\n</blockquote>\n\n<p>While cholesterol is easily synthesised by humans, its presence in the blood is equally equated with bad! Low cholesterol and low synthesis of vitamin D are <a href=\"http://www.translationalres.com/article/S1931-5244(08)00272-7/abstract\" rel=\"nofollow noreferrer\">plain</a> to see and taking drugs <a href=\"https://www.sciencedirect.com/science/article/pii/S014067360668971X\" rel=\"nofollow noreferrer\">interfering</a> with cholesterol metabolism – or eating cholesterol lowering food (more fibre please!) – might influence vitamin D synthesis. These relations are <a href=\"https://link.springer.com/article/10.1007/s10557-009-6182-7\" rel=\"nofollow noreferrer\">currently</a> <a href=\"https://pdfs.semanticscholar.org/b8a5/61c971a32362d02914f5bed50f0070207306.pdf\" rel=\"nofollow noreferrer\">contested</a> in heated debates with <a href=\"https://www.jclinepi.com/article/S0895-4356(02)00504-8/abstract\" rel=\"nofollow noreferrer\">differing</a> views.</p>\n\n<p>If a citizen is obese, and those are said to increase in number and weight:</p>\n\n<blockquote>\n <p><a href=\"https://onlinelibrary.wiley.com/doi/full/10.1038/oby.2011.404\" rel=\"nofollow noreferrer\">Andjela T. Drincic: \"Volumetric Dilution, Rather Than Sequestration Best Explains the Low Vitamin D Status of Obesity\"</a> 2012 <a href=\"https://doi.org/10.1038/oby.2011.404\" rel=\"nofollow noreferrer\">https://doi.org/10.1038/oby.2011.404</a> </p>\n</blockquote>\n\n<p>As one review summarised it:</p>\n\n<blockquote>\n <p><strong>Results</strong><br>\n The definition of vitamin D insufficiency and deficiency, as well as assay methodology for 25-hydroxyvitamin D or 25(OH)D, vary between studies. However, serum 25(OH)D levels below 75 nmol/L are prevalent in every region studied whilst levels below 25 nmol/L are most common in regions such as South Asia and the Middle East. Older age, female sex, higher latitude, winter season, darker skin pigmentation, less sunlight exposure, dietary habits, and absence of vitamin D fortification are the main factors that are significantly associated with lower 25(OH)D levels.<br>\n <sub><a href=\"https://link.springer.com/article/10.1007/s00198-009-0954-6\" rel=\"nofollow noreferrer\">A. Mithal et al.: \"Global vitamin D status and determinants of hypovitaminosis D\", Osteoporosis International, November 2009, Volume 20, Issue 11, pp 1807–1820.</a> </sub></p>\n</blockquote>\n\n<h2>Conclusion</h2>\n\n<p>Closer to the poles people need to have relatively: paler skin, more D in their food, adequate cholesterol levels, and more time in the sun at the right time with enough skin area exposed to meet the estimated demands for vitamin D. During winter it is almost impossible to meet the demand with UVB rays alone.</p>\n", "score": 7 } ]
16,586
CC BY-SA 4.0
General Population Low Vitamin D Levels
[ "vitamin-d", "sun-exposure", "sunlight", "sunscreen-sunblock", "spf-sun-protection-factor" ]
<p>In the answer to <a href="https://medicalsciences.stackexchange.com/questions/16576/is-it-advisable-to-wear-uv-protected-swimsuit-that-covers-arms-and-legs-for-skin">Is it advisable to wear UV protected swimsuit that covers arms and legs for skin protection to an outdoor swimming pool?</a> by @Anko, it was stated that you can get enough vitamin D from a few minutes sunlight and this is supported by Cancer Research UK (<a href="https://www.nice.org.uk/guidance/ph32/documents/expert-paper-3-vitamin-d2" rel="nofollow noreferrer">2010</a>)</p> <p>Yet, in a British Nutrition Foundation Nutrition Bulletin (<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4288313" rel="nofollow noreferrer">Spiro &amp; Buttriss, 2014</a>), it is pointed out that there are reports of inadequate vitamin D status in Europe and this may be a problem elsewhere because:</p> <blockquote> <p>In the northern hemisphere at latitudes <a href="https://en.wikipedia.org/wiki/40th_parallel_north" rel="nofollow noreferrer">greater than around 40°N</a> (north of Madrid, see Table 1), sunlight is not strong enough to trigger synthesis of vitamin D in the skin from October to March.</p> </blockquote> <p>You could say that this can be reflected in the southern hemisphere at <a href="https://en.wikipedia.org/wiki/40th_parallel_south" rel="nofollow noreferrer">latitudes South of 40°S</a> in <strong>possibly</strong> the April to September months, due to the seasonal differences North and South of the equator. The thing with that is, in the Southern hemisphere, it wouldn't affect a great deal of people in comparison, as 40°S is between the islands of New Zealand and cuts off a small tip of South America.</p> <p>What I am wondering is, if Cancer Research UK has adequately proved that you can get enough vitamin D from a few minutes sunlight, has there been definitive evidence to suggest why there is an inadequate vitamin D status in Europe?</p> <h2>References</h2> <p>Cancer Research UK. (2010). <em>Vitamin D expert review</em>. Available at: <a href="http://www.nice.org.uk/nicemedia/live/11871/49665/49665.pdf" rel="nofollow noreferrer">http://www.nice.org.uk/nicemedia/live/11871/49665/49665.pdf</a></p> <p>Spiro, A., &amp; Buttriss, J. L. (2014). Vitamin D: an overview of vitamin D status and intake in Europe. <em>Nutrition bulletin</em>, 39(4), 322-350.<br>DOI: <a href="https://doi.org/10.1111/nbu.12108" rel="nofollow noreferrer">10.1111/nbu.12108</a> PMCID: <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4288313" rel="nofollow noreferrer">PMC4288313</a> PMID: <a href="https://www.ncbi.nlm.nih.gov/pubmed/25635171" rel="nofollow noreferrer">25635171</a><br>Free PDF: <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4288313/pdf/nbu0039-0322.pdf" rel="nofollow noreferrer">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4288313/pdf/nbu0039-0322.pdf</a></p>
9
https://medicalsciences.stackexchange.com/questions/16861/after-a-dog-bite-why-are-vaccines-given-in-multiple-injections-rather-than-a-si
[ { "answer_id": 17727, "body": "<h2>Brief background</h2>\n<p>There are 2 major types of vaccines, passive and active vaccines. Passive vaccines are simply &quot;antibodies&quot; to fight off disease and active vaccines are &quot;dead/weakened/components(e.g. proteins)&quot; of the offending agent to allow your body to produce your own antibodies.</p>\n<hr />\n<p>Same is true for <a href=\"https://www.cdc.gov/vaccines/vpd/tetanus/index.html\" rel=\"noreferrer\">anti tetanus</a>, (which may come in different mixtures) tetanus toxoid is an active vaccine which is given to adults if it has been 10 years from your previous booster or unrecalled date of the last dose. Tetanus immune globulin(igtet) is the passive form. For anti-rabies, we use ARV(anti-rabies vaccine/active) and ERIG/HRIG(passive vaccine)</p>\n<p><strong>-HARRISON'S principles of Internal Medicine 18th ed Tetanus pg. 1199</strong></p>\n<p>In short, you may take at least 2-4 injections depending on your previous vaccinations and <a href=\"http://www.who.int/news-room/fact-sheets/detail/rabies\" rel=\"noreferrer\">what category your animal bite injury is.</a></p>\n<hr />\n<h2>Mixing vaccines in one syringe</h2>\n<blockquote>\n<p>&quot;No vaccines should ever be mixed in the same syringe unless the\ncombination has been specifically approved by the FDA.&quot;\n-<a href=\"http://www.immunize.org/askexperts/administering-vaccines.asp\" rel=\"noreferrer\">immunize.org</a></p>\n</blockquote>\n<p> </p>\n<blockquote>\n<p>It is prudent to give in separate limbs (if possible), so there is no\nconfusion about which vaccine caused an allergic reaction.\n-<a href=\"http://www.immunize.org/askexperts/administering-vaccines.asp\" rel=\"noreferrer\">immunize.org</a></p>\n</blockquote>\n<p> </p>\n<blockquote>\n<p>&quot;Diluting or mixing a biological product with other components or\nrepackaging a biological product by removing it from its approved\ncontainer-closure system and transferring it to another\ncontainer-closure system is highly likely to affect the safety or\neffectiveness of the biological product&quot; -FDA <a href=\"https://www.google.com.ph/url?sa=t&amp;source=web&amp;rct=j&amp;url=https://www.fda.gov/downloads/drugs/guidances/ucm434176.pdf&amp;ved=2ahUKEwjVm6T82ZfeAhUIoVMKHcvIDcAQFjAMegQIBhAB&amp;usg=AOvVaw3JhXSylUhGgpxA-lWJ5Zxn\" rel=\"noreferrer\">link to FDA protocol,\nPDF\nfile</a></p>\n</blockquote>\n<hr />\n<h2>Giving vaccines on a schedule <sub>(lifted from OP's provided link)</sub></h2>\n<blockquote>\n<p>&quot;The rabies vaccine is made up of the dead rabies virus. When it is\ninjected into your body, your immune system it immediately starts to\nproduce antibodies to fight off the perceived infection. Multiple\nshots ensure that the levels of antibodies remain elevated so that\neven if the live virus is already in your system, the antibodies will\nneutralize it.&quot;</p>\n<p><strong>-HARRISON'S principles of Internal Medicine 18th ed Rabies pg. 1615</strong></p>\n</blockquote>\n<hr />\n<h2>References</h2>\n<p>Cdc.gov, immunize.org, who.int, fda.gov</p>\n<hr />\n<h2>P.S.</h2>\n<p>The anti-tetanus vaccine schedule is in the provided link and I lifted the answer from OP to give a short preview of the answer. A total of 3-5 injections if we include antibiotics.</p>\n", "score": 8 } ]
16,861
CC BY-SA 4.0
After a dog bite, why are vaccines given in multiple injections rather than a single injection containing multiple vaccines?
[ "prescription", "rabies", "animal-bites", "tetanus-shot" ]
<p>When a dog bites a person, why is it necessary to take about 5 injections or needles? Why not just one big injection?</p> <p>Do they all have the same medicine? Or does each one have its own medicine? </p> <p>Is the time between them important? I see on the internet different periods such as (the first one should be taken immediately, the second one is after 3 days, then once per week) and you can find other different sequences.</p> <p>My research is:</p> <ol> <li>The immediate vaccine is <a href="https://patient.info/health/travel-vaccinations-leaflet/rabies-vaccine" rel="nofollow noreferrer">human rabies-specific immunoglobulin (HRIG)</a> and this explains the first shot. Vaccination is also for Rabies, Tetanus, and maybe some other bacteria. For me, this means one or two more injections. One for Rabies and Tetanus and One for the other bacteria or whatever the combination is. This is a total of 3 injections including the immediate one. So why the 5 injections? I mean what could be the other diseases/bacteria? </li> <li><p><em>Is it possible to take all the vaccines through one big shot?</em> I know it depends on the amount/size of each vaccine. Or maybe it is required to wait for a few days to reduce the side effects or whatever the reason is, right? <a href="https://www.quora.com/Why-is-a-rabies-vaccine-a-single-shot-for-dogs-but-a-multi-course-ordeal-for-people-1" rel="nofollow noreferrer">This source compares dog vaccine to human vaccine so it's not that related and I can't find useful sources.</a> I'm not talking about inventing new techniques like <a href="https://www.sciencedaily.com/releases/2009/09/090918181532.htm" rel="nofollow noreferrer">this one</a>. I just wonder why don't we combine/mix the 5 or 6 injections together.</p></li> <li><p><a href="https://thehealthorange.com/stay-happy/holistic-living/rabies-vaccination-happens-miss-injection/" rel="nofollow noreferrer">The number of injections vary from one case to another</a>. That's why I think that only the first injection has a different solution but the other successive injections have the same solution/medicine, right? At the same time, some sources say these successive injections are different because they are for different medicines like Tetanus...etc. So I got confused.</p></li> <li>I knew the answer to the third question. Yes, the time is important and a delay of 1 to 2 days is considered acceptable as your antibody levels will still be high enough to fight off an infection. </li> </ol>
9
https://medicalsciences.stackexchange.com/questions/17108/why-is-there-no-toxoplasmosis-vaccine
[ { "answer_id": 17482, "body": "<p>Short answer, loaded with opinion: Inherent difficulties present but mainly not enough resources allocated to this problem until now.</p>\n\n<p>Longer version, based on other expert opinions and research results –– or really: challenges: </p>\n\n<p>The reasoning in the question is indeed plausible and puzzling. It should be easy, on the face of it. Only that this pathogen is widespread and comparatively mild, making other venues seemingly more pressing. But there were attempts, illustrating some problems along the way:</p>\n\n<blockquote>\n <p>Toxoplasmosis, caused by an intracellular protozoan parasite, Toxoplasma gondii, is widespread throughout the world. The disease is of major medical and veterinary importance, being a cause of congenital disease and abortion in humans and domestic animals. In addition, recently it has gained importance owing to toxoplasma encephalitis in AIDS patients. In the last few years, there has been considerable progress towards the development of a vaccine for toxoplasmosis, and a vaccine based on the live-attenuated S48 strain was developed for veterinary uses. However, this vaccine is expensive, causes side effects and has a short shelf life. Furthermore, <strong>this vaccine may revert to a pathogenic strain and, therefore, is not suitable for human use.</strong> Various experimental studies have shown that it may be possible to develop a vaccine against human toxoplasmosis. Recent progress in knowledge of the protective immune response generated by T. gondii and the current status of development of a vaccine for toxoplasmosis are highlighted.</p>\n \n <p><a href=\"https://www.ncbi.nlm.nih.gov/pubmed/19485758\" rel=\"noreferrer\">Kur J, Holec-Gasior L, Hiszczyńska-Sawicka E.: \"Current status of toxoplasmosis vaccine development.\", Expert Rev Vaccines. 2009 Jun;8(6):791-808</a>. doi: 10.1586/erv.09.27.</p>\n</blockquote>\n\n<p>Even if relatively mild, introducing pathogenic elements is unethical. And may not sell that well?</p>\n\n<p>Among the reasons for the difficulties encountered were:</p>\n\n<blockquote>\n <ul>\n <li>Lack of efficacious protective antigen candidates</li>\n <li>Lack of detailed understanding of pathogenic, immune and host cell invasion mechanisms</li>\n <li>Insufficient advanced research techniques and theories of immunology or vaccinology</li>\n <li>Can DNA vaccines fulfill their promise?</li>\n <li>Biosafety of DNA vaccines</li>\n <li>Immune tolerance and allergy problems of DNA vaccines</li>\n <li>The efficacy of DNA vaccines</li>\n </ul>\n \n <p><a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3579912/\" rel=\"noreferrer\">Qi Liu, Lachhman Das Singla, and Huaiyu Zhou: \"Vaccines against Toxoplasma gondii: Status, challenges and future directions\", Hum Vaccin Immunother. 2012 Sep 1; 8(9): 1305–1308.</a> doi: 10.4161/hv.21006</p>\n</blockquote>\n\n<p>Research is not standing still on this front. Especially DNS vaccines seem to have made some progress:</p>\n\n<blockquote>\n <p>Toxoplasma gondii (T. gondii) is an obligate intracellular protozoan parasite that infects all warm-blooded animals including humans and causes toxoplasmosis. An effective vaccine could be an ideal choice for preventing and controlling toxoplasmosis. T. gondii Superoxide dismutase (TgSOD) might participate in affecting the intracellular growth of both bradyzoite and tachyzoite forms. In the present study, the TgSOD gene was used to construct a DNA vaccine (pEGFP-SOD).</p>\n \n <p>The present study revealed that the DNA vaccine triggered strong humoral and cellular immune responses, and aroused partial protective immunity against acute T. gondii infection in BALB/c mice. The collective data suggests the SOD may be a potential vaccine candidate for further development.</p>\n \n <p><a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5463464/\" rel=\"noreferrer\">Yuan Liu et al.: \"Immunization with a DNA vaccine encoding Toxoplasma gondii Superoxide dismutase (TgSOD) induces partial immune protection against acute toxoplasmosis in BALB/c mice\", BMC Infect Dis. 2017; 17: 403.\n Published online 2017 Jun 7.</a> doi: 10.1186/s12879-017-2507-5</p>\n</blockquote>\n\n<p>These are promising but still quite preliminary. Whether looking at live or live-attenuated vaccines, protein vaccines, DNS vaccines, epitope vaccines, carbohydrate vaccines, exosome vaccines, RNA vaccines or possible adjuvants, a big bunch of ideas is considered, developed and tested for. Only that they really lack a base of attack.</p>\n\n<p>One of the latest reviews in the field summarises it:</p>\n\n<blockquote>\n <p>Despite continuous research efforts, there are still very few effective strategies against toxoplasmosis. In the past few years, numerous vaccination experiments have been performed to control T. gondii infection.</p>\n \n <p>In this review, the authors summarize the development of T. gondii vaccines with proper adjuvants, ranging from live or live-attenuated vaccines to protein vaccines, DNA vaccines, epitope vaccines and novel vaccines. They also highlight the challenges involved in the development of T. gondii vaccines, including specific impediments and shortcomings.</p>\n \n <p>Expert opinion: Moving towards the development of effective vaccines against T. gondii is not only a tedious mission but also a difficult challenge. Future studies should consider new approaches and strategies for vaccine development, particularly novel vaccines and genetic adjuvants, as well as optimizing immunization protocols and evaluation criteria.</p>\n \n <p><a href=\"https://www.tandfonline.com/doi/abs/10.1080/14712598.2018.1413086\" rel=\"noreferrer\">Yawen Li &amp; Huaiyu Zhou: \"Moving towards improved vaccines for Toxoplasma gondii\", Expert Opinion on Biological Therapy, Volume 18, 2018 - Issue 3,</a> <a href=\"https://doi.org/10.1080/14712598.2018.1413086\" rel=\"noreferrer\">https://doi.org/10.1080/14712598.2018.1413086</a></p>\n</blockquote>\n\n<p>The unsound base from which most of this research is fishing in the dark is that neither the life cycle nor the actual most of invasion/infection are fully understood. Not in the least because there are quite a few strains in the wild, some much more pathogenic than others.</p>\n\n<p>The last cited review opinion closes with:</p>\n\n<blockquote>\n <p>In our view, directions for future research should focus on the development of an effective cat vaccine. Such a vaccine would prevent oocyst shedding by cats and reduce oocyst contamination of the environment and risk to animals and humans. The priority is to develop a live-attenuated vaccine using non-reverting mutants. With the wide use of CRISPR technology, generating gene deletion mutants as live vaccines has become feasible and provides a novel approach for the control of toxoplasmosis. Therefore, it is expected that several years will be required before an effective vaccine against T. gondii is ready and available.</p>\n</blockquote>\n", "score": 7 } ]
17,108
CC BY-SA 4.0
Why is there no toxoplasmosis vaccine?
[ "vaccination", "parasites", "toxoplasmosis" ]
<p>I assume there is some misunderstanding on my part about the vaccine-creation-process and which factors play a role in it. Below is my current understanding.</p> <p><strong>About toxoplasmosis:</strong></p> <p>Toxoplasmosis is a disease that can infect both humans and cats. It doesn't have a lot of symptoms, i.e. if you have it, you might not even notice. After you have had it, you are immune to further infection because your body has toxoplasmosis-antibodies now.</p> <p>Toxoplasmosis is dangerous in one situation: if a pregnant woman gets it, it may cause disabilities in the baby (even at later ages when he/she grows up) or even abortion. This can only happen if the woman has not had the disease earlier in life, because then she would be immune. (It's also dangerous for people with a weakened immune system, such as hiv-patients, but you can't vaccinate them anyway so let's disregard them for this question.)</p> <p><strong>About vaccines:</strong></p> <p>Vaccines are weakened or dead virusses/microbes that cause a certain disease. The body recognises them as a threat, makes the appropriate antibodies and remembers these antibodies in case it encounters this disease again. When the non-weakened disease shows up, the body doesn't need the time to invent/create the antibodies anymore, so it can start to destroy the disease before it becomes too strong.</p> <p>This only works for diseases for which your body can invent antibodies (given enough time), for which it will remember the antibodies and for which the pathogens don't evolve fast.</p> <p><strong>My question:</strong></p> <p>Why is there no toxoplasmosis-vaccine available? It seems toxoplasmosis is an ideal vaccine-candidate: the body can create antibodies and will remember them. The pathogen doesn't even need to be dead or weakened, since the symptoms for the disease are so low. It seems to me that this vaccine would be "just" inserting the toxoplasmosis-germs into the patients blood.</p> <p>I'm thinking about a vaccine for women who are not pregnant. Obviously inserting toxoplasmosis into pregnant women is a bad idea.</p> <p><strong>Possibilities that I thought of:</strong></p> <ul> <li><p>The toxoplasmosis is caused by a parasite, which may be too big of a difference with virusses/mirobes to create a vaccine out of? But why would that be harder?</p></li> <li><p>Toxoplasmosis may have annoying pathogens, that don't want to survive and reproduce in a lab, so you'd have to hunt the parasites down in "the wild" for every vaccine, which doesn't seem to be feasible.</p></li> <li><p>Something causes such a vaccine to be too expensive for the hasstle.</p></li> <li><p>Nobody wants to fund research to create such a vaccine, because other diseases are more dangerous.</p></li> </ul> <p>Related question: <a href="https://health.stackexchange.com/questions/16033/why-are-some-viruses-harder-to-make-vaccines-for">https://health.stackexchange.com/questions/16033/why-are-some-viruses-harder-to-make-vaccines-for</a> but this question asks for all possible reasons why a vaccine can not be created. I'm interested specifically in toxoplasmosis.</p>
9
https://medicalsciences.stackexchange.com/questions/17546/has-the-infamous-j-shaped-curve-with-regard-to-alcohol-consumption-and-life-ex
[ { "answer_id": 17548, "body": "<blockquote>\n<p>To date, there has been no randomized clinical trial of low‐volume alcohol consumption that has assessed any mortality outcome. Therefore, the literature about the mortality effects of alcohol consumption consists entirely of observational studies.</p>\n<p><sup>Source: Naimi, Timothy S. et al. <strong><a href=\"https://onlinelibrary.wiley.com/doi/full/10.1111/add.13451\" rel=\"noreferrer\">Selection biases in observational studies affect associations between ‘moderate’ alcohol consumption and mortality. Addiction</a></strong>. Volume 112, Issue 2, February 2017, p. 207-214</sup></p>\n</blockquote>\n<p>This is important to note. All studies, including the ones cited by me and LangLangC, are observational meta-analyses. They take census data and data from other studies and do some statistical calculations with that. Those are accurate, but it is tricky to avoid selection biases, and without a clinical trial, one can only show correlation and not causation. Even with double-blind randomly controlled trials (RCTs), one can run into biases and common factors that fake causation.</p>\n<p>As an example for this case: Maybe most 'moderate' drinkers are wealthy (they can afford a bit of alcohol and upper-class drinking, but are well-educated enough not to become addicts) and thus have more access to health services, hence decreasing their morbidity in comparison to other groups. This doesn't mean that drinking moderately is healthy, but that being wealthy is healthy.</p>\n<p>With that being said:</p>\n<h2>Yes, it has been disproven</h2>\n<p>A recent article published in The Lancet which is the largest meta analysis to date has a very comprehensive overview of risks associated with moderate to high-level drinking. The J-curve only exists for very few hand-picked risks:</p>\n<p><a href=\"https://i.stack.imgur.com/nnihB.jpg\" rel=\"noreferrer\"><img src=\"https://i.stack.imgur.com/nnihB.jpg\" alt=\"enter image description here\" /></a></p>\n<p>While small amounts of alcohol might decrease the risk of ischaemic heart diseases and diabetes, the cumulative risk is increasing for every quantity of alcohol consumed.</p>\n<p>In a sense, it doesn't help you if you are at half the risk of dying from a heart attack when the risk of having a seizure is tripled (greatly simplified).\n<a href=\"https://i.stack.imgur.com/GevRJ.jpg\" rel=\"noreferrer\"><img src=\"https://i.stack.imgur.com/GevRJ.jpg\" alt=\"\" /></a></p>\n<p>The study itself is quite comprehensive and not that difficult to understand, so I highly recommend a read-through. It has been covered by most newspapers as well, but not all news coverage was accurate.</p>\n<blockquote>\n<p>Griswold, Max G, et al. “<strong><a href=\"https://www.thelancet.com/action/showPdf?pii=S0140-6736%2818%2931310-2\" rel=\"noreferrer\">Alcohol Use and Burden for 195 Countries and Territories, 1990–2016: a Systematic Analysis for the Global Burden of Disease Study 2016.</a></strong>” The Lancet, vol. 392, no. 10152, 2018, pp. 1015–1035.</p>\n</blockquote>\n<p>This is even more convincing as there seems to be a selection bias favouring 'moderate' drinkers.</p>\n<blockquote>\n<p>After reviewing the possible sources of selection bias in observational studies about the relationship between low‐volume alcohol consumption and mortality, <strong>selection bias is another reason to suggest that existing research may overestimate protective effects systematically from ‘moderate’ alcohol consumption.</strong> There are a number of sources of selection bias inherent in comparing established low‐volume drinkers with non‐drinkers. Low‐volume drinkers who are enrolled into studies constitute a particular group of drinkers who chose to begin drinking, tolerated or enjoyed its effects, did not die prior to study enrollment, did not become heavy drinkers, did not stop drinking and were of sufficient physical and mental capacity to be enrolled into studies several decades after drinking initiation. <strong>Overall, most sources of selection bias favour low‐volume drinkers in relation to non‐drinkers.</strong> Studies that attempt to address these types of bias generally find attenuated or non‐significant relationships between low‐volume alcohol consumption and cardiovascular disease, which is the major source of possible protective effects on mortality. <strong>Furthermore, observed mortality effects among established low‐volume drinkers are of limited relevance to health‐related decisions about whether to begin drinking or whether to continue drinking purposefully into old age.</strong></p>\n<p><sup>Source: Naimi, Timothy S. et al. <strong><a href=\"https://onlinelibrary.wiley.com/doi/full/10.1111/add.13451\" rel=\"noreferrer\">Selection biases in observational studies affect associations between ‘moderate’ alcohol consumption and mortality. Addiction</a></strong>. Volume 112, Issue 2, February 2017, p. 207-214</sup></p>\n</blockquote>\n<hr />\n<h2>Discussion</h2>\n<p>Prompted by LangLangC's excellent answer, I wanted to expand my answer a bit. The study I cited mainly proves that the relative risk is monotonic increasing: At no level of alcohol consumption, the overall relative risk is smaller than at any previous level. The J-shaped curve does exist for a few risks (mainly associated with cardiovascular diseases).</p>\n<p>What conclusions should one draw from this?</p>\n<ul>\n<li>Shifting from 1 standard drink to 0 standard drinks does not seem all too sensible, one does not gain a significant decrease of relative risk but does loose some quality of life</li>\n<li><strong>Shifting from 0 standard drinks to 1 standard drink also doesn't seem sensible, as one does not gain a significant increase of relative risk either</strong>.</li>\n</ul>\n<p>The second implication needs to be true in order for the J-curve claim to be valid, and hence I consider it disproven.</p>\n", "score": 9 }, { "answer_id": 18331, "body": "<p>No. \"The J-curve\" was not recently disproven, but the evidence for it slightly\nmodified. The correlational observation is still that no and low amounts of drinking do not have seriously negative health outcomes associated with them.</p>\n\n<p>What has changed is what conclusions campaigners for \"zero alcohol\" draw from that evidence.</p>\n\n<p>We do not have any evidence that any intervention on that level has positive consequences: either recommendations of moving from zero to one or from two to zero seems to not be founded on firm evidence. Only going lower from high is.</p>\n\n<hr>\n\n<p>It seems to depend on the way the observational, epidemiological and correlational data is used. That is: how the data is gathered, analysed and interpreted. And how puritan the belief systems of the researchers are.</p>\n\n<p>Drinking large amounts of alcohol is bad. Doing that daily is bad.\nA relative recent study amassed a huge dataset and concluded that the only safe amount of alcohol is zero. This got even published in The Lancet as </p>\n\n<blockquote>\n <p><a href=\"https://doi.org/10.1016/S0140-6736(18)31310-2\" rel=\"nofollow noreferrer\">\"Alcohol use and burden for 195 countries and territories, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016\"</a> </p>\n</blockquote>\n\n<p>The key findings are communicated in the extreme, globally, and badly:</p>\n\n<blockquote>\n <p>Analysing data from 15 to 95-year-olds, the researchers compared people who did not drink at all with those who had one alcoholic drink a day.<br>\n They found that out of 100,000 non-drinkers, 914 would develop an alcohol-related health problem such as cancer or suffer an injury.<br>\n But an extra four people would be affected if they drank one alcoholic drink a day.<br>\n For people who had two alcoholic drinks a day, 63 more developed a condition within a year and for those who consumed five drinks every day, there was an increase of 338 people, who developed a health problem.</p>\n</blockquote>\n\n<p>That is from a baseline of 914 problems in 100000 people an increase to 918 people in 100000 for one drink a day. As one can see, problems usually related to alcohol develop in 914 non-drinkers already or as well and one drink a day means trouble for an additional 4 people.</p>\n\n<p>Is much or not? If that is difficult to picture mentally, The Lancet provides you the service of a picture that gets overlooked in the sensationalist press:</p>\n\n<blockquote>\n <p><a href=\"https://i.stack.imgur.com/PGMyk.jpg\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/PGMyk.jpg\" alt=\"enter image description here\"></a></p>\n</blockquote>\n\n<p>The relative risk increase – in a study that claims zero is the only safe level – for one drink per day is effectively zero as well.</p>\n\n<p>This study aims at scare mongering and has to admit that </p>\n\n<blockquote>\n <p>Alcohol use is a leading risk factor for death and disability, but its overall association with health remains complex given the possible protective effects of moderate alcohol consumption on some conditions. </p>\n</blockquote>\n\n<p>This study still does not challenge \"moderate alcohol consumption may be preventive for some conditions such as ischaemic heart disease and diabetes\" but looks at the effects associated with each individual health outcome together with level of alcohol consumption. When those inferences are then combined into an aggregate according to the author's model we arrive at the picture above.</p>\n\n<blockquote>\n <p>Specifically, comparing no drinks with one drink a day the risk of developing one of the 23 alcohol-related health problems was 0.5% higher — meaning 914 in 100,000 15–95 year olds would develop a condition in one year if they did not drink, but 918 people in 100,000 who drank one alcoholic drink a day would develop an alcohol-related health problem in a year. </p>\n \n <p>This increased to 7% in people who drank two drinks a day (for one year, 977 people in 100,000 who drank two alcoholic drinks a day would develop an alcohol-related health problem) and 37% in people who drank five drinks every day (for one year, 1252 people in 100,000 who drank five alcoholic drinks a day would develop an alcohol-related health problem).</p>\n</blockquote>\n\n<p>How do experts judge this data? </p>\n\n<blockquote>\n <p><a href=\"http://www.sciencemediacentre.org/expert-reaction-to-systematic-analysis-of-the-health-impacts-of-alcohol/\" rel=\"nofollow noreferrer\">David Spiegelhalter, Winton Professor for the Public Understanding of Risk at the University of Cambridge, said</a>:</p>\n \n <p>“According to data provided by the authors but not published in the paper, to suffer one extra alcohol-related health problem, around 1,600 people would need to drink two drinks totalling 20g (2.5 units) of alcohol a day for a year. This is equivalent to around 32 standard 70cl bottles of gin over a year, so a total of 50,000 bottles of gin among these 1,600 people is associated with one extra health problem. <strong>This indicates a very low level of harm in moderate drinkers, and suggests UK guidelines of an average of 16g a day (2 units) are very low-risk indeed.</strong></p>\n \n <p>“Given the pleasure presumably associated with moderate drinking, claiming there is no ‘safe’ level does not seem an argument for abstention. There is no safe level of driving, but government do not recommend that people avoid driving. Come to think of it, there is no safe level of living, but nobody would recommend abstention.”</p>\n</blockquote>\n\n<p>This same year another Lancet paper tried to tackle the problem:</p>\n\n<blockquote>\n <p><a href=\"https://doi.org/10.1016/S0140-6736(18)30134-X\" rel=\"nofollow noreferrer\">Angela M Wood et al.: \"Risk thresholds for alcohol consumption: combined analysis of individual-participant data for 599 912 current drinkers in 83 prospective studies\", Volume 391, Issue 10129, p1513-1523, April 14, 2018</a><br>\n Low-risk limits recommended for alcohol consumption vary substantially across different national guidelines. To define thresholds associated with lowest risk for all-cause mortality and cardiovascular disease, we studied individual-participant data from 599 912 current drinkers without previous cardiovascular disease.<br>\n <strong>In current drinkers of alcohol in high-income countries, the threshold for lowest risk of all-cause mortality was about 100 g/week.</strong> For cardiovascular disease subtypes other than myocardial infarction, there were no clear risk thresholds below which lower alcohol consumption stopped being associated with lower disease risk. These data support limits for alcohol consumption that are lower than those recommended in most current guidelines.</p>\n</blockquote>\n\n<p>Again, a call \"to lower guidelines\". Despite the result that for some outcomes the lowest risk was <em>not</em> \"zero drinks\" but that the relative risk increases, clearly, if you go below 100g of pure alcohol a week! </p>\n\n<blockquote>\n <p>From the <a href=\"https://www.thelancet.com/cms/10.1016/S0140-6736(18)30134-X/attachment/5b9e9977-5741-4caf-9ab1-ab873eef63fc/mmc1.pdf\" rel=\"nofollow noreferrer\">supplementary material</a>: (click to enlarge)<br>\n <a href=\"https://i.stack.imgur.com/Qc0U2.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/Qc0U2s.png\" alt=\"enter image description here\"></a>\n <a href=\"https://i.stack.imgur.com/H4bV0.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/H4bV0s.png\" alt=\"enter image description here\"></a>\n <a href=\"https://i.stack.imgur.com/UUzrf.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/UUzrfs.png\" alt=\"enter image description here\"></a>\n <a href=\"https://i.stack.imgur.com/wZ6T8.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/wZ6T8s.png\" alt=\"enter image description here\"></a></p>\n</blockquote>\n\n<p>Do these numbers really suggest that not drinking alcohol – either never or even worse to quit drining – is to be seen as a potential risk factor? The huge difference between never-drinkers and ex-drinkers might spoil that party a bit. An equally plausible explanation for that is that dislike for alcohol might be a sign for already frail or future health problems. </p>\n\n<h1>Summary</h1>\n\n<p>The vast majority of findings show that moderate drinking (definitions of that may vary as much as does individual tolerance) is associated with a low risk and that there is an ultimately unexplained correlation between drinking a bit and slightly longer life expectancy. The <a href=\"https://en.wikipedia.org/wiki/French_paradox\" rel=\"nofollow noreferrer\">French Paradox</a> keeps on giving.</p>\n", "score": 5 } ]
17,546
CC BY-SA 4.0
Has the (in)famous J-shaped curve with regard to alcohol consumption and life expectancy been finally disproven?
[ "alcohol", "life-expectancy" ]
<p>Firstly: I am aware of the other question: <a href="https://medicalsciences.stackexchange.com/questions/585/is-moderate-alcohol-consumption-beneficial-for-maximizing-life-expectancy">Is moderate alcohol consumption beneficial for maximizing life expectancy?</a></p> <p>Nevertheless, this question dates to 2015, and the recent campaign of medical authorities against alcohol consumption in any quantities is a, well, recent thing. This I believe mandates a newer question.</p> <p>Shame on me for not being able to find the source; but I DO recall seing an article about the J-shaped curve - the (purpoted?) correlation that moderate alcohol use increases the life expectation relative to teetotallers. I must've read this article a year ago or so, and the article itself is likely even older. The article claimed that:</p> <ul> <li>Attempts were made to invalidate the J-shaped curve by pointing out that teetotallers' life expectancy is reduced by the presence of former alcohol addicts in this group;</li> <li>The studies were repeated, explicitly removing former alcohol addicts from the group of teetotallers, and the J-shaped curve persisted.</li> </ul> <p>Nonetheless, as we can see, nowadays we have multiple claims from medical authorities that alcohol is harmful in any quantities, that even moderate or light drinking does one no good and that to minimize risk, a consumption of 0g of ethanol should be recommended.</p> <p>Has the J-shaped curve been finally conclusively disproven then?</p> <p>EDIT: A late addition, but I've FINALLY found the source of my claim that studies that removed former alcohol addicts from the group of teetotallers still shew the J-shaped curve: <a href="http://content.time.com/time/magazine/article/0,9171,2017200,00.html" rel="nofollow noreferrer">http://content.time.com/time/magazine/article/0,9171,2017200,00.html</a></p>
9
https://medicalsciences.stackexchange.com/questions/18639/does-skeletal-muscle-injury-cause-hypertrophy-or-atrophy
[ { "answer_id": 23691, "body": "<p>The answer is hypertrophy, but if the injury is disabling, then it will lead to muscle atrophy due to disuse. Note that body builders lift weight until causing minor injury.</p>\n\n<p><a href=\"https://www.unm.edu/~lkravitz/Article%20folder/musclesgrowLK.html\" rel=\"nofollow noreferrer\">https://www.unm.edu/~lkravitz/Article%20folder/musclesgrowLK.html</a></p>\n", "score": 1 } ]
18,639
CC BY-SA 4.0
Does skeletal muscle injury cause hypertrophy or atrophy?
[ "muscle", "injury", "pathophysiology", "muscular-atrophy" ]
<p>In the following diagram from the <em>Love and Bailey</em> textbook I see that injury causes a decrease in hypertrophy due to a decrease in the expression of IGF-1. Here <em>Love and Bailey</em> consider a skeletal muscle model.</p> <p><a href="https://i.stack.imgur.com/vSY29.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/vSY29.jpg" alt="From Love and Bailey"></a></p> <p>But in <em>Robbins and Cotran</em> (diagram attached), mechanical stretch and growth factors like IGF-1 cause an increase in contractile protein synthesis. Here <em>Robbins and Cotran</em> consider a heart muscle as model.</p> <p><a href="https://i.stack.imgur.com/dZDfM.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dZDfM.jpg" alt="From Robbins and Cotran"></a></p> <p>So the question is whether injury causes hypertrophy or atrophy? I feel that if injury is beyond repair then atrophy should occur, but is this what <em>Love and Bailey</em> wanted to say or is it different? Does it depend on whether the muscle is skeletal muscle or cardiac muscle?</p>
9
https://medicalsciences.stackexchange.com/questions/19998/videos-of-surgery
[ { "answer_id": 20003, "body": "<p>Top quality resources for videos will be found at sites from surgical academies, which often offer free or low-price subscriptions to students/residents/trainees:</p>\n\n<ul>\n<li><strong>American College of Surgeons</strong> curriculum for residents at <a href=\"https://cine-med.com/acsonline/\" rel=\"noreferrer\">https://cine-med.com/acsonline/</a></li>\n<li><strong>American College of Surgeons Journal</strong> at <a href=\"https://www.journalacs.org/featuredvideo\" rel=\"noreferrer\">https://www.journalacs.org/featuredvideo</a></li>\n<li><strong>Journal of Trauma and Acute Care Surgery</strong> at <a href=\"https://journals.lww.com/jtrauma/Pages/videogallery.aspx\" rel=\"noreferrer\">https://journals.lww.com/jtrauma/Pages/videogallery.aspx</a></li>\n<li><strong>Society of American Gastrointestinal and Endoscopic Surgeons</strong> at <a href=\"https://www.sages.org/video/\" rel=\"noreferrer\">https://www.sages.org/video/</a></li>\n<li><strong>American College of Obstetricians and Gynecologists</strong> at <a href=\"https://cfweb.acog.org/onlinevideos/\" rel=\"noreferrer\">https://cfweb.acog.org/onlinevideos/</a></li>\n</ul>\n\n<p>Other sites I have not thoroughly explored but appear to offer quite a bit:</p>\n\n<ul>\n<li><a href=\"https://medschool.ucsd.edu/som/surgery/divisions/trauma-burn/training/videos/Pages/Videos.aspx\" rel=\"noreferrer\">https://medschool.ucsd.edu/som/surgery/divisions/trauma-burn/training/videos/Pages/Videos.aspx</a></li>\n<li><a href=\"https://www.csurgeries.com/\" rel=\"noreferrer\">https://www.csurgeries.com/</a></li>\n</ul>\n\n<p>Uncertain of quality:</p>\n\n<ul>\n<li><a href=\"https://medtube.net/\" rel=\"noreferrer\">https://medtube.net/</a></li>\n</ul>\n\n<p><strong>Regarding desensitization</strong> to blood, surgery, trauma, deliveries, and the like, watching videos definitely will help. However, there is nothing that can replace the real thing - especially when you are actively involved in the cutting, cleaning, suctioning, retracting, stretching, etc. Be very aware of this, and consider spending time shadowing in the ER or OR as an observer (i.e. able to leave at any time) before you need to take an active role in the procedure.</p>\n\n<p>Therefore additionally, I want to encourage you that if you are expected to be part of a surgical team and know there is a possibility that you may experience nausea/vomiting, lightheadedness, or syncope: <strong>it is your professional and ethical responsibility to inform t</strong>he chief resident and/or attending, as well as the circulating and/or scrub nurse, <strong>so that they can plan for your replacement if anything happens.</strong> </p>\n\n<p>Secondly, the <strong>second that you notice symptoms or feel you are becoming overwhelmed, it is imperative that you tell the person who will replace you,</strong> hand over your task, and remove yourself from the surgical field. Sit right there on the floor if you have to, but try to avoid (1) faceplanting into the open surgical field of the patient's body or (2) fainting in the trauma bay or OR and hitting your head on the tile floor, becoming a trauma patient yourself. I had classmates with such stories and it was horrifically embarrassing for them. </p>\n\n<p>Instead, be more like a certain medical student who told their attending and the circulating nurse that they'd done extensive desensitization training but this was their first real surgical case. So then after a prolonged surgery with heavy blood loss, when they overheated after sweating for hours in the scrub suit and began to vaso-vagal, someone was already scrubbed in to take over for them immediately - and they could remove themselves to a safe spot to sit. Rather than be humiliated by contaminating the field or becoming a patient themself, they were thanked for being responsible and self aware.</p>\n", "score": 12 } ]
19,998
CC BY-SA 4.0
Videos of surgery
[ "surgery", "practice-of-medicine", "trauma", "video" ]
<p>Where can I find a website which contains videos of open trauma (HD if possible)? I want to accustom to these views (because I am a medical student).</p>
9
https://medicalsciences.stackexchange.com/questions/20030/cartilage-deterioration-in-patients-after-acl-reconstruction-in-contralateral-k
[ { "answer_id": 23129, "body": "<p>So there are two aspects to cartilage degeneration after an ACL injury, what they call post-traumatic osteoarthritis (PTOA): the first is the increase in knee laxity after ACL reconstruction and the second are inflammatory molecules within the synovium that surrounds the ACL and cartilage. So while people may overcompensate on their other leg temporarily while they are recovering, there are many causes of OA in the ACL deficient knee that are not present in the contralateral knee. </p>\n\n<ol>\n<li>They have found that all current reconstructive methods, whether it is tendon grafts (for example using the hamstring tendon) or bone-tendon-bone grafts (use of the patellar tendon) do not restore the kinematics of the knee back to baseline. There is joint laxity that occurs due to the improper healing between the graft and the bone tunnels that are created in order to secure the ACL in place. That laxity causes increased load and stress onto the cartilage on the femur and tibia, and, therefore, causing osteoarthritis. <a href=\"https://journals-sagepub-com.ezproxy.med.cornell.edu/doi/10.1177/0363546507307396\" rel=\"nofollow noreferrer\">https://journals-sagepub-com.ezproxy.med.cornell.edu/doi/10.1177/0363546507307396</a></li>\n<li>There are many pro-inflammatory molecules that are released within the knee capsule after both the initial injury and the reconstruction that have been shown to contribute to the development of OA in the injured knee. In order to not get too in depth, I wont mention all of them, but Tumor necrosis factor-alpha (TNF-alpha) is the one that persisted in the injured knee for <strong>years</strong> after the ACL reconstruction.The presence of this pro-inflammatory molecule indicates that there is still processes going on that increase the degradation of cartilage through several processes. <a href=\"https://linkinghub.elsevier.com/retrieve/pii/S1063-4584(14)01250-3\" rel=\"nofollow noreferrer\">https://linkinghub.elsevier.com/retrieve/pii/S1063-4584(14)01250-3</a></li>\n</ol>\n\n<p>So yes, people who undergo ACL reconstruction may have different gaits that cause them to maybe develop OA in the contralateral knee (especially without proper physical therapy) very far down the road, but this probability is smaller than the injured leg due to the factors that I have listed above. That is why the percentage of OA is so much higher in the injured leg than the contralateral leg. My research is in the healing process of ACL reconstruction, so I don't feel entirely qualified to answer that part, hopefully someone else can touch on that aspect of your question! Hope this helped</p>\n", "score": 3 } ]
20,030
CC BY-SA 4.0
Cartilage deterioration in patient&#39;s after ACL reconstruction in contralateral knee
[ "gait-walk-abnormalities", "osteoarthritis", "acl-ligament", "cartilage" ]
<p>From literature, about 50% of anterior cruciate ligament (ACL) reconstruction patient's are predisposed to osteoarthritis (OA) later in life due to cartilage deterioration and cartilage damage from the injury<a href="http://sciencedirect.com/science/article/pii/S0966636212000082" rel="noreferrer"> [Source 1</a> and <a href="http://journals.sagepub.com/doi/10.1177/0363546507307396" rel="noreferrer">source 2]</a>. From my understanding, patient's, if they develop OA, typically only develop it in their injured leg as opposed to the contralateral.</p> <p>If they are avoiding weight on their injured leg and mainly using their contralateral leg, shouldn't they experience some cartilage deterioration in the contralateral as well due to the gait asymmetry? Is it because they did not have cartilage damage from the injury in that leg?</p> <p>I am an engineering student studying biomechanics, but I am trying to understand the importance and relationships between ACL reconstruction and development of OA.</p> <p>While we're here, also the injured leg experiences decreased knee flexion angle after injury. Does this affect cartilage deterioration if you are applying less forces from the flexion?</p>
9
https://medicalsciences.stackexchange.com/questions/21200/is-there-any-figure-about-the-accuracy-of-covid-19-tests
[]
21,200
Is there any figure about the accuracy of COVID-19 tests?
[ "virus", "test", "test-results", "covid-19" ]
<p>Recently I saw the local media (Romania) presenting a case that was initially considered COVID-19 positive and two subsequent tests led to negative results. As far as I know no official bothered to offer an explanation and I assume that this is expected in some cases (e.g. initial test was not done correctly).</p> <p>Like any other tests, I expect to have an accuracy &lt; 100% and I am wondering what that accuracy is for current tests.</p> <p>I have read here about <a href="https://futurism.com/neoscope/coronavirus-covid19-test-kits-broken-america-scarce-china" rel="noreferrer">the issues with US tests</a> and <a href="https://www.channelnewsasia.com/news/asia/how-china-tests-for-covid-19-coronavirus-12438008" rel="noreferrer">this article</a> shows how tests are done in China:</p> <blockquote> <p>(..) the main way to test patients is using the Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) technique.</p> </blockquote> <p><a href="https://pubmed.ncbi.nlm.nih.gov/8862813-quantitative-rt-pcr-limits-and-accuracy/" rel="noreferrer">This paper</a> deals with RT-PCR accuracy, but I cannot understand its conclusions.</p> <p><sub>By accuracy I mean (total tests - false positives - false negatives) / total tests.</sub></p> <p>Is there any figure about the accuracy of COVID-19 tests?</p>
9
https://medicalsciences.stackexchange.com/questions/21252/is-there-any-identified-policy-china-is-doing-to-successfully-reduce-covid-19-th
[ { "answer_id": 23419, "body": "<h1>To Mask or not To Mask that is the question</h1>\n<p>One thing China did early on was wearing face masks to protect others. They are still doing it today even though there has been <a href=\"https://www.aljazeera.com/news/2020/04/no-covid-19-deaths-10-days-chinas-wuhan-200425154631443.html\" rel=\"nofollow noreferrer\">no deaths for 10 days</a> and most new cases (counted in dozens and not 10s of thousands like USA today) are <a href=\"https://www.usnews.com/news/world/articles/2020-04-24/china-reports-12-new-coronavirus-cases-no-new-deaths\" rel=\"nofollow noreferrer\">imported rather than community spread</a>. This picture from a couple days ago:</p>\n<p><a href=\"https://i.stack.imgur.com/JdgOu.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/JdgOu.png\" alt=\"coronavirus china face masks.png\" /></a></p>\n<p>Source: <a href=\"https://www.upi.com/Top_News/World-News/2020/04/25/Global-coronavirus-death-toll-hits-200000-China-reports-10-days-of-no-deaths/8211587816006/?ur3=1\" rel=\"nofollow noreferrer\">https://www.upi.com/Top_News/World-News/2020/04/25/Global-coronavirus-death-toll-hits-200000-China-reports-10-days-of-no-deaths/8211587816006/?ur3=1</a></p>\n<p>However Delaware's Governor John Carney just ordered today all citizens to wear masks starting this coming Tuesday (April 28, 2020):</p>\n<ul>\n<li><a href=\"https://www.mrt.com/news/article/New-order-requires-Delaware-residents-to-wear-15226421.php\" rel=\"nofollow noreferrer\">New order requires Delaware residents to wear face coverings</a></li>\n</ul>\n<p>So slowly but surely America is starting to do some of the things that China has done.</p>\n", "score": 2 } ]
21,252
CC BY-SA 4.0
Is there any identified policy China is doing to successfully reduce COVID-19 the other countries aren&#39;t using?
[ "covid-19", "public-health", "health-policy" ]
<p>Over the last days (beginning of March 2020), active cases of COVID-19 from China have dropped at a rate of 1,000-2,000 per day. China is the only country which seems able to reduce the amount of active cases, assuming the information which is coming from China is true. </p> <p>Is there any identified policy China is doing to successfully reduce COVID-19, that other countries aren't using?</p>
9
https://medicalsciences.stackexchange.com/questions/21510/which-diy-mask-is-most-effective
[ { "answer_id": 21566, "body": "<h1>DIY Designs - most do not carry efficacy data claims</h1>\n\n<p>Note that many of these are only respiratory protection designs. You also need to protect your eyes in a high risk situation eg. looking after an infected relative. Get protective goggles or your own glasses and attach a plastic shield eg. plastic pamphlet holder to the glasses for a full face shield.</p>\n\n<h2>Combined mask with face shield</h2>\n\n<h3>University of Hong Kong-Shenzen Paper Towel Mask</h3>\n\n<ul>\n<li>Claims 90% filter protection of a surgical mask</li>\n</ul>\n\n<p><a href=\"https://www.youtube.com/watch?v=aNjpH5lBZ8w\" rel=\"nofollow noreferrer\">https://www.youtube.com/watch?v=aNjpH5lBZ8w</a></p>\n\n<h2>Masks only</h2>\n\n<h3>Freesewing sew your own mask from cotton T-shirt etc</h3>\n\n<p><a href=\"https://freesewing.org/fu-facemask-freesewing.org.a4.pdf\" rel=\"nofollow noreferrer\">A4 PDF Pattern</a></p>\n\n<h3>CDC letter - simple mask (uses heavyweight T shirt material)</h3>\n\n<p><a href=\"https://wwwnc.cdc.gov/eid/article/12/6/05-1468_article\" rel=\"nofollow noreferrer\">CDC</a></p>\n\n<h3>Instructables Cloth Masks patterns</h3>\n\n<ul>\n<li>as with all cloth based, wash in hot water to pre-shrink</li>\n</ul>\n\n<p><a href=\"https://www.instructables.com/id/DIY-Cloth-Face-Mask/\" rel=\"nofollow noreferrer\">Instructables</a></p>\n\n<h3>Copper 3D design using PLA 3-D printer</h3>\n\n<ul>\n<li>seems to need their special filter but perhaps use HEPA material?</li>\n</ul>\n\n<p><a href=\"https://www.infoq.com/news/2020/03/3d-n95-masks/\" rel=\"nofollow noreferrer\">3d printed masks unsafe</a> poor fit or build up of CO2</p>\n\n<p><a href=\"https://copper3d.com/hackthepandemic/\" rel=\"nofollow noreferrer\">Instructions</a></p>\n\n<h2>Face shield only</h2>\n\n<ul>\n<li><p><a href=\"https://www.prusaprinters.org/prints/25857-prusa-protective-face-shield-rc2\" rel=\"nofollow noreferrer\">Prusa Printers RC2</a></p></li>\n<li><p><a href=\"https://budmen.com/?elqTrackId=946352961b79457dbc8531c8fd75da1a&amp;elqaid=4271&amp;elqat=2\" rel=\"nofollow noreferrer\">Budmen 3D Printed Face Sheild V2</a></p></li>\n<li><p><a href=\"http://www.amlab.co.nz/shield.html\" rel=\"nofollow noreferrer\">Laser Cut Shield - University of Auckland</a></p></li>\n</ul>\n\n<h2>Field Respirators</h2>\n\n<p><a href=\"https://enable.hp.com/us-en-3dprint-COVID-19-containment-applications\" rel=\"nofollow noreferrer\">First industrialized field 3D printed emergency respiration device to support hospitals and ICUs. </a></p>\n\n<h2>Door Handle Opener</h2>\n\n<ul>\n<li>Hands free <a href=\"https://www.materialise.com/en/hands-free-door-opener?elqTrackId=20b7e0f7116d499a97ad8f3b66dabb8b&amp;elqaid=4271&amp;elqat=2\" rel=\"nofollow noreferrer\">Materialise Door handle Opener</a></li>\n</ul>\n\n<h3>More Reading</h3>\n\n<p><a href=\"https://smartairfilters.com/en/blog/best-materials-make-diy-face-mask-virus/\" rel=\"nofollow noreferrer\">https://smartairfilters.com/en/blog/best-materials-make-diy-face-mask-virus/</a></p>\n", "score": 8 }, { "answer_id": 21669, "body": "<p>Here is a relevant link on the best materials to use in creating a handmade face mask:</p>\n\n<p><a href=\"https://www.cambridge.org/core/journals/disaster-medicine-and-public-health-preparedness/article/testing-the-efficacy-of-homemade-masks-would-they-protect-in-an-influenza-pandemic/0921A05A69A9419C862FA2F35F819D55\" rel=\"nofollow noreferrer\">https://www.cambridge.org/core/journals/disaster-medicine-and-public-health-preparedness/article/testing-the-efficacy-of-homemade-masks-would-they-protect-in-an-influenza-pandemic/0921A05A69A9419C862FA2F35F819D55</a></p>\n\n<p>Also, here is relevant study on the effectiveness of a saline solution applied to a face mask that can kill flu-like viruses (through the osmotic effect) even within five minutes:</p>\n\n<p><a href=\"https://www.thestar.com/news/canada/2020/02/11/salt-is-the-secret-ingredient-in-these-face-masks-that-could-prevent-spread-of-next-coronavirus.html\" rel=\"nofollow noreferrer\">https://www.thestar.com/news/canada/2020/02/11/salt-is-the-secret-ingredient-in-these-face-masks-that-could-prevent-spread-of-next-coronavirus.html</a></p>\n\n<p><a href=\"https://www.nature.com/articles/srep39956\" rel=\"nofollow noreferrer\">https://www.nature.com/articles/srep39956</a></p>\n", "score": 2 }, { "answer_id": 23818, "body": "<p>There is literature to support that wearing a mask decreases transmission of infection ([Leung, N.H.L., Chu, D.K.W., Shiu, E.Y.C. et al. Respiratory virus shedding in exhaled breath and efficacy of face masks. Nat Med 26, 676–680 (2020).<a href=\"https://doi.org/10.1038/s41591-020-0843-2\" rel=\"nofollow noreferrer\">1</a>), however, there is exceedingly limited evidence that wearing an improvised mask is anywhere near as effective as standard protective equipment (N95 respirator or better).</p>\n\n<p>However, with that said, although I wear a powered air purifying respirator at work (and my company owns the equipment specifically for my personal use, so I could in theory use it elsewhere), I use a homemade cotton mask when outside of home for routine tasks (shopping, getting the vehicle fixed, etc.).</p>\n\n<p>As others have said, wearing a mask is for protection of others from droplets that you might generate, and as such these masks function similar to how the surgical mask was designed (to protect the patient from the surgeon, not vice versa). If everyone was to wear a mask, this could be compared to the concept of \"herd immunity\" where people are protecting each other. It is a bigger concept than purely personal protection, which an improvised mask fails at any way you wish to look at it.</p>\n", "score": 2 }, { "answer_id": 21671, "body": "<p>In a scenario of being forced to choose from DIY designs (yikes!): Perhaps understanding: How are masks tested for efficacy? would provide insight into comparing DIY mask designs. </p>\n\n<p>Efficacy Test example: <a href=\"https://www.astm.org/Standards/F2101.htm\" rel=\"nofollow noreferrer\">https://www.astm.org/Standards/F2101.htm</a></p>\n\n<p>Possible Mask features that drive efficacy:</p>\n\n<ul>\n<li>physical design: does the design effectively position the filter?</li>\n<li>filter material &amp; design: Which materials will work better than others?</li>\n<li>comfort: Will users be able to wear these for extended periods without discomfort?</li>\n</ul>\n", "score": 1 }, { "answer_id": 21754, "body": "<p>From {1}:</p>\n\n<p><a href=\"https://i.stack.imgur.com/rnHgo.png\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/rnHgo.png\" alt=\"enter image description here\"></a></p>\n\n<hr>\n\n<p>References:</p>\n\n<ul>\n<li>{1} 2020-03-25 - Stanford COVID-19 Evidence Service - Addressing COVID-19 Face Mask Shortages [v1.2] <a href=\"https://archive.org/details/20200325stanfordcovid19evidenceserviceaddressingcovid19facemaskshortagesv1.2\" rel=\"nofollow noreferrer\">https://archive.org/details/20200325stanfordcovid19evidenceserviceaddressingcovid19facemaskshortagesv1.2</a></li>\n</ul>\n", "score": 0 } ]
21,510
CC BY-SA 4.0
Which DIY mask is most effective?
[ "covid-19", "personal-protective-equipment" ]
<p>There have been a number of do-it-yourself (DIY) mask designs released and tested by both universities and other institutions on account of world wide Personal Protection Equipment (PPE) shortages. Some were designed at the time of the SARS epidemic, and use double-folded kitchen paper towels with tissue.</p> <p>Even though double tea towel masks are more effective in reducing viral exposure, it's difficult to breathe with it on.</p> <p>What design has been tested to provide relatively good protection while being comfortable to wear and breathe while wearing them? And it needs to use readily available materials throughout the world.</p>
9
https://medicalsciences.stackexchange.com/questions/23565/what-data-and-research-is-available-on-the-mortality-risk-infection-fatality-ra
[ { "answer_id": 23568, "body": "<p>Well, there is one meta-analytical estimate of the IFR for Covid-19 out already albeint only as a <a href=\"https://www.medrxiv.org/content/10.1101/2020.05.03.20089854v1\" rel=\"noreferrer\">draft paper</a>:</p>\n\n<blockquote>\n <p>there were 13 estimates of IFR included in the final meta-analysis, from a wide range of countries, published between February and April 2020. The meta-analysis demonstrated a point-estimate of IFR of 0.75% (0.49-1.01%) with significant heterogeneity (p&lt;0.001). Conclusion: Based on a systematic review and meta-analysis of published evidence on COVID-19 until the end of April, 2020, the IFR of the disease across populations is 0.75% (0.49-1.01%). However, due to very high heterogeneity in the meta-analysis, it is difficult to know if this represents the \"true\" point estimate. It is likely that different places will experience different IFRs. More research looking at age-stratified IFR is urgently needed to inform policy-making on this front.</p>\n</blockquote>\n\n<p>A couple of additional points from the paper:</p>\n\n<blockquote>\n <p>Analysing by country of origin did not appear to have a substantial effect on the findings, with both those studies from within and outside of China showing similar aggregate estimates [...] There was very significantly lower heterogeneity in studies published using Chinese data (I<sup>2</sup> = 0%, p>0.5)</p>\n</blockquote>\n\n<p>On the other hand, they found that IFR estimates (insofar) increased by month, in April in particular, although this refers to the date of publication of the study rather than the time interval spanned by the study's observations. (Personally, I find this a little intriguing, as during the H1N1/09 pandemic, I've <a href=\"https://medicalsciences.stackexchange.com/questions/21035/in-what-time-frame-exactly-was-the-2009-h1n1-fatality-rate-overestimated\">read</a>--albeit not in great detail-- that the CFR estimates mostly went down over time.)</p>\n\n<p><a href=\"https://i.stack.imgur.com/UwxPt.png\" rel=\"noreferrer\"><img src=\"https://i.stack.imgur.com/UwxPt.png\" alt=\"enter image description here\"></a></p>\n\n<p>There's a summary table with the exact findings of each of the 13 studies at the end of this meta-analysis. Alas it's in a somewhat too gaudy of a format to include here; that table spans 5 pages in the draft paper.</p>\n", "score": 6 }, { "answer_id": 23567, "body": "<p>Below is a summary of all data and findings answering this question meeting the question criteria which I have found or which have been pointed out in answers to this question. The mortality risk given is that provided in the research paper cited, or, where no paper is cited (sources 6,7 and 9), the number of deaths divided by number of infections based on the raw data.</p>\n<ol>\n<li>'Estimates of the severity of coronavirus disease 2019: a model-based analysis'. Robert Verity, PhD et al.<br />\n<a href=\"https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(20)30243-7/fulltext\" rel=\"nofollow noreferrer\">https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(20)30243-7/fulltext</a></li>\n</ol>\n<p><strong>Mortality risk (overall) = 0.657%</strong></p>\n<p><strong>Mortality risk (age stratified):</strong><br />\n0–9 = 0.00161%<br />\n10–19 = 0.00695%<br />\n20–29 = 0.0309%<br />\n30–39 = 0.0844%<br />\n40–49 = 0.161%<br />\n50–59 = 0.595%<br />\n60–69 = 1.93%<br />\n70–79 = 4.28%<br />\n≥80 = 7.80%</p>\n<hr />\n<ol start=\"2\">\n<li>LA COUNTY PUBLIC HEALTH DEPARTMENT / UNIVERSITY OF SOUTHERN CALIFORNIA STUDY FINDINGS.<br />\n<a href=\"https://qz.com/1841445/covid-19-may-be-undercounted-50-fold-in-la-antibody-surveys-show/\" rel=\"nofollow noreferrer\">https://qz.com/1841445/covid-19-may-be-undercounted-50-fold-in-la-antibody-surveys-show/</a><br />\n<a href=\"https://reason.com/2020/04/20/l-a-county-antibody-tests-suggest-the-fatality-rate-for-covid-19-is-much-lower-than-people-feared/\" rel=\"nofollow noreferrer\">https://reason.com/2020/04/20/l-a-county-antibody-tests-suggest-the-fatality-rate-for-covid-19-is-much-lower-than-people-feared/</a><br />\nInfections (in US, extrapolated) = 221,00 to 442,000.<br />\nAge factors: Age adjusted estimate for entire US population.</li>\n</ol>\n<p><strong>Mortality risk (IFR) = 0.1% - 0.3%.</strong></p>\n<hr />\n<ol start=\"3\">\n<li>GANGELT, GERMANY STUDY.<br />\n<a href=\"https://www.land.nrw/sites/default/files/asset/document/zwischenergebnis_covid19_case_study_gangelt_0.pdf\" rel=\"nofollow noreferrer\">https://www.land.nrw/sites/default/files/asset/document/zwischenergebnis_covid19_case_study_gangelt_0.pdf</a><br />\n<a href=\"https://www.technologyreview.com/2020/04/09/999015/blood-tests-show-15-of-people-are-now-immune-to-covid-19-in-one-town-in-germany/?fbclid=IwAR1P-zqpfx6ATyVsGYa_9EHVgr3aY0ryKDh_uuC90xKtXMWXKR4fR4OMYKI\" rel=\"nofollow noreferrer\">https://www.technologyreview.com/2020/04/09/999015/blood-tests-show-15-of-people-are-now-immune-to-covid-19-in-one-town-in-germany/?fbclid=IwAR1P-zqpfx6ATyVsGYa_9EHVgr3aY0ryKDh_uuC90xKtXMWXKR4fR4OMYKI</a><br />\nAge factors: Age adjusted estimate for entire adult population of Gangelt.<br />\nInfections (approx.) = 2% of adult population of Gangelt.</li>\n</ol>\n<p><strong>Estimated mortality risk (IFR) = 0.37%</strong></p>\n<hr />\n<ol start=\"4\">\n<li>DIAMOND PRINCESS OUTBREAK.<br />\n<a href=\"https://www.statista.com/statistics/1099517/japan-coronavirus-patients-diamond-princess/\" rel=\"nofollow noreferrer\">https://www.statista.com/statistics/1099517/japan-coronavirus-patients-diamond-princess/</a><br />\nDate of last possible infection: March 1st, 2020<br />\nDeaths to date: 13\nDiamond Princess study #1 (Mortality risk):<br />\n'Estimating the infection and case fatality ratio for COVID-19 using age-adjusted data from the outbreak on the Diamond Princess cruise ship'. Timothy W Russell et al.<br />\n<a href=\"https://www.medrxiv.org/content/10.1101/2020.03.05.20031773v2\" rel=\"nofollow noreferrer\">https://www.medrxiv.org/content/10.1101/2020.03.05.20031773v2</a><br />\nAverage age: Age adjusted estimate for entire population of China.<br />\nCI= 95%.</li>\n</ol>\n<p><strong>Estimated mortality risk (IFR) = 0.5%</strong></p>\n<p>Diamond Princess study #2 (infections estimate):<br />\n‘The contribution of asymptomatic SARS-CoV-2 infections to transmission -a model-based analysis of the Diamond Princess outbreak’. Jon C . Emery et al.<br />\n<a href=\"https://cmmid.github.io/topics/covid19/reportsEmery_Transmission%20from%20asymptomatic%20SARS-CoV-2.pdf\" rel=\"nofollow noreferrer\">https://cmmid.github.io/topics/covid19/reportsEmery_Transmission%20from%20asymptomatic%20SARS-CoV-2.pdf</a><br />\nAverage age = 65.<br />\nTotal estimated infections: 1,304 (1,198-1,416).</p>\n<p><strong>Mortality risk (IFR) based on mean infections estimate= 0.99%</strong></p>\n<hr />\n<ol start=\"5\">\n<li>MORTALITY RISK ESTIMATE FROM JEAN-DOMINQUE MICHEL.<br />\n<a href=\"https://phusis.ch/2020/03/25/covid-19-il-sagit-dune-epidemie-banale/\" rel=\"nofollow noreferrer\">https://phusis.ch/2020/03/25/covid-19-il-sagit-dune-epidemie-banale/</a><br />\nAge factors: Statistics cited for entire population of china as of time of publishing (25th March, 2020).</li>\n</ol>\n<p><strong>Mortality risk (IFR) =&lt; 0.3%</strong></p>\n<hr />\n<ol start=\"6\">\n<li>STOCKHOLM STUDY.<br />\nInfections data: ‘Estimates of the peak-day and the number of infected individuals during the covid-19 outbreak in the Stockholm region, Sweden.<br />\nFebruary – April 2020’.<br />\n<a href=\"https://www.folkhalsomyndigheten.se/publicerat-material/publikationsarkiv/e/estimates-of-the-peak-day-and-the-number-of-infected-individuals-during-the-covid-19-outbreak-in-the-stockholm-region-sweden-february--april-2020/\" rel=\"nofollow noreferrer\">https://www.folkhalsomyndigheten.se/publicerat-material/publikationsarkiv/e/estimates-of-the-peak-day-and-the-number-of-infected-individuals-during-the-covid-19-outbreak-in-the-stockholm-region-sweden-february--april-2020/</a><br />\nType: Modelling based estimate.<br />\nCI: Unknown.<br />\nDeaths data: <a href=\"https://c19.se/en/Sweden/Stockholm\" rel=\"nofollow noreferrer\">https://c19.se/en/Sweden/Stockholm</a>.<br />\nAge factors: Age adjusted estimate for entire population of Stockholm.<br />\nNumber of infections as of April 8th, 2020 = 70,500<br />\nNumber of deaths as of May 1st, 2020 = 1,417.</li>\n</ol>\n<p><strong>Mortality risk (IFR)= 2%</strong></p>\n<hr />\n<ol start=\"7\">\n<li>USS THEODORE ROOSEVELT OUTBREAK.<br />\n<a href=\"https://navylive.dodlive.mil/2020/03/15/u-s-navy-covid-19-updates/\" rel=\"nofollow noreferrer\">https://navylive.dodlive.mil/2020/03/15/u-s-navy-covid-19-updates/</a><br />\nOutbreak arrival date: 24th March, 2020.<br />\nNumber of infections = 2,141<br />\nNumber of deaths = 1<br />\nAverage age = ?</li>\n</ol>\n<p><strong>Mortality risk (IFR) = 0.046%</strong></p>\n<hr />\n<ol start=\"8\">\n<li>DRAFT OF META-STUDY ESTIMATING IFR OF CORONAVIRUS.<br />\n'A systematic review and meta-analysis of published research data on COVID-19 infection-fatality rates', Gideon Meyerowitz-Katz et al.<br />\n<a href=\"https://www.medrxiv.org/content/10.1101/2020.05.03.20089854v1\" rel=\"nofollow noreferrer\">https://www.medrxiv.org/content/10.1101/2020.05.03.20089854v1</a><br />\nAge factors: Meta-study based on studies with varying age groups/average ages. Average age of meta-study not indicated.</li>\n</ol>\n<p><strong>Estimated mortality risk = 0.75% (0.49-1.01%)</strong></p>\n<hr />\n<ol start=\"9\">\n<li>CHARLES DE GAULLE AIRCRAFT CARRIER OUTBREAK.<br />\n<a href=\"https://en.wikipedia.org/wiki/COVID-19_pandemic_on_Charles_de_Gaulle\" rel=\"nofollow noreferrer\">https://en.wikipedia.org/wiki/COVID-19_pandemic_on_Charles_de_Gaulle</a><br />\nArrival date: April 10th.<br />\nAverage age = ?<br />\nNumber of infections = 1,046<br />\nDeaths: 0</li>\n</ol>\n<p><strong>Mortality risk (IFR) = 0%</strong></p>\n<hr />\n<ol start=\"10\">\n<li>Bulletin of the World Health Organization, 99 (‎1)‎: 19 - 33F, Ioannidis, John P A. (‎2021)‎. <em>Infection fatality rate of COVID-19 inferred from seroprevalence data.</em></li>\n</ol>\n<p><strong>Generalized Mortality Risk (IFR): 0.23%</strong></p>\n<hr />\n", "score": 2 }, { "answer_id": 23716, "body": "<p><strong>Around 1 to 2%</strong>.</p>\n\n<p>While @Fizz and @Dale Newton have already provided a nice collection (with statistics even), I'd like to add one more, which is based on <strong>common sense as well as statistics</strong>.</p>\n\n<p>First off, the source should be such that it could reasonably be expected to report truthful data; that pretty much means democratic governments which are taking this seriously and not trying to minimize it for various reasons. Second, the number of infections (as the most likely source of error) should be estimated from as large a dataset as possible; so only data from countries that have a <em>very</em> large ratio of tests to positive results, and a rigorous test program. Third, the test should have a sensitivity and specificity which is well known.</p>\n\n<p>The one source that best meets these criteria is <strong>South Korea</strong>. <a href=\"https://www.statista.com/topics/6082/coronavirus-covid-19-in-south-korea/\" rel=\"nofollow noreferrer\">South Korea</a> has done 802k tests, found 11142 confirmed infections, and had 264 deaths (as of 2020-05-22), for a raw infection fatality rate of <strong>2.37%</strong>.</p>\n\n<p>Australia and New Zealand both provide approximate confirmation of the South Korea-based estimate. <a href=\"https://www.health.gov.au/sites/default/files/documents/2020/05/coronavirus-covid-19-at-a-glance-coronavirus-covid-19-at-a-glance-infographic_21.pdf\" rel=\"nofollow noreferrer\">Australia</a> has done 1192k tests, found 7106 confirmed infections, and had 102 deaths, for an IFR of <strong>1.43%</strong>. <a href=\"https://www.health.govt.nz/our-work/diseases-and-conditions/covid-19-novel-coronavirus/covid-19-current-situation/covid-19-current-cases\" rel=\"nofollow noreferrer\">New Zealand</a> has done 259k tests, found 1504 confirmed infections, and had 21 deaths, for an IFR of <strong>1.39%</strong>.</p>\n\n<p>In South Korea, the ratio of tests to confirmed infections at 72:1 is very high; Australia and New Zealand are even higher, but (perhaps) with less good tracing. The definition of \"confirmed\" is a positive PCR test, with a positive re-test. South Korea also has a <a href=\"https://www.businessinsider.com/south-korea-contact-tracing-helped-control-nightclub-outbreak-2020-5\" rel=\"nofollow noreferrer\">robust contact tracing program</a>, and surveilance for people presenting with symptoms which would be suspicious even if not linked to a known cluster. Recently, just one new case led to running 45k tests on possible contacts. Of course that doesn't mean they've caught <em>every single</em> infection, but they would not be far from it; it is reasonable to think they have found most of the infections, symptomatic or not. \"Most\" is a bit hard to quantify, but over 50% is virtually certain, and over 80% is quite likely.</p>\n\n<p>The 2.37% fatality rate is quite disturbingly high, and much higher than most other reports, but it does in my opinion come from the most trustworthy (and largest) dataset. There are a few things that may account for that: demographics (older population), most cases occured quite early in the timeline (less worldwide experience on effective treatment), or possibly a few large clusters that just happened to be in an older population; and yes, of course they missed some infections. Because of that I think it's reasonable to think a population-average infection fatality rate ought to be a bit lower; 1% to 2% is a good common-sense range. A somewhat earlier but more detailed South Korean report including demographics is here: <a href=\"https://www.medrxiv.org/content/10.1101/2020.03.15.20036368v1.full.pdf\" rel=\"nofollow noreferrer\">https://www.medrxiv.org/content/10.1101/2020.03.15.20036368v1.full.pdf</a> (if anyone can find a more recent one, please add a link to it)</p>\n\n<p>I consider most of the sources collected in other answers as <strong>not credible</strong>, for various reasons. The Lancet article is based primarily on Chinese data. The LA County study was done by Eran Bendavid (who did the similarly flawed Santa Clara study which was thoroughly trashed by just about everyone <a href=\"https://www.mercurynews.com/2020/04/20/feud-over-stanford-coronavirus-study-the-authors-owe-us-all-an-apology/\" rel=\"nofollow noreferrer\">link</a> <a href=\"https://www.nationalgeographic.com/science/2020/05/why-unreliable-tests-are-flooding-the-coronavirus-conversation-cvd/\" rel=\"nofollow noreferrer\">link</a> and subsequently retracted), used an antibody test that may have a fairly high false positive rate (which itself is based on a <em>tiny</em> validation data set; 3 false positives out of 401 known negative samples) and found 35 positives out of 863 (also quite small sample). Common sense says that conclusions based on a whole country's worth of data and based on ultra-reliable PCR tests trumps conclusions based on a few hundred tests based on unreliable antibodies, any day. Similarly, all of the studies cited in Meyerowitz-Katz's meta-analysis linked above either (a) draw conclusions from a tiny number of cases/infections/tests, or (b) use completely unreliable methods to estimate the rate of infections, or both.</p>\n\n<p>I would give the whole-country data from South Korea (and other countries with thorough testing) a huge weight in any meta-analysis; data from large seroconversion studies a medium weight (but there aren't any of those yet); and small seroconversion studies (or studies that just estimate prevalence using models) essentially no weight. <strong>I think trying to claim we know a more precise rate than the 1-2% range I described, or that the rate is significantly less than 1% for an average population, is simply not supported by the data available now.</strong></p>\n\n<p><strong>NOTE</strong> This assumes a health care system which is not overwhelmed. For an example of what happens if the system is overwhelmed, see Italy: also from Statista, Lombardy had 228k tests, 86k reported infections, 15.8k deaths. The ratio of tests to positive results is less than 3:1; the infection fatality rate based on <em>known</em> infections is 18%. How many total infections were there that are not counted? Well, Italian data on seroconversion is pretty sparse, but at least <a href=\"https://www.medrxiv.org/content/10.1101/2020.05.11.20098442v1\" rel=\"nofollow noreferrer\">one source</a> says 4-11% (presumably: 400k to 1.1M infections in Lombardy, with very wide error bars). That gives an IFR of 2 to 5% (also with very wide error bars).</p>\n", "score": 1 } ]
23,565
CC BY-SA 4.0
What data and research is available on the mortality risk (infection fatality rate) of COVID-19?
[ "covid-19", "research", "death", "covid-19-datasets", "mortality-rate" ]
<p>Given controversy and confusion over aspects of COVID-19, particularly over comparisons and contrasts with the mortality risk of seasonal flu, this question seeks data and findings on the <strong>mortality risk (Infection Fatality Rate) of Covid-19</strong>.</p> <p>The mortality risk, or Infection fatality rate (IFR), sometimes known as ‘mortality rate’, ‘death rate’, or 'lethality' represents the risk of dying after contracting the virus, and is calculated as the number of deaths divided by the number infections.</p> <p>The mortality risk (IFR) of COVID-19 is often overlooked in mainstream news media, which tends to focus on the case fatality rate (number of deaths divided by the number of CASES), or falsely equate/conflate the two.</p> <p>The case fatality rate is in itself not a valid indicator of the mortality risk of a virus as it does not account for unreported/asymptomatic cases and therefore the true number of infections, or estimates of them. Hence the interest in data/studies on the mortality risk.</p> <p>Ref:<br /> <a href="https://medicalxpress.com/news/2020-05-team-covid-infection-fatality.html" rel="nofollow noreferrer">https://medicalxpress.com/news/2020-05-team-covid-infection-fatality.html</a><br /> <a href="http://jdmichel.blog.tdg.ch/archive/2020/03/24/covid-19-the-game-is-over-305275.html?fbclid=IwAR2xfWuLuVodAVLk8bZ9VzDTGsa_7CS0B0xmlZw6AqskRNRjjGLDAi4Mp2c" rel="nofollow noreferrer">http://jdmichel.blog.tdg.ch/archive/2020/03/24/covid-19-the-game-is-over-305275.html?fbclid=IwAR2xfWuLuVodAVLk8bZ9VzDTGsa_7CS0B0xmlZw6AqskRNRjjGLDAi4Mp2c</a></p> <p><strong>Source / information criteria</strong>:</p> <p>For the purposes of this question, all answers must come with specific, referenced data/findings based on (or at least explicitly indicating) the <strong>number of infections</strong> (either directly known through testing of the entire study population, as in confinement/isolation situations, or based on modeled/estimated/extrapolated number of infections), and the <strong>number of deaths</strong> in each case.</p> <p>This question <strong>does not</strong> seek answers containing personal estimates from respondents, and sources providing guesses based on anecdotal evidence or impressions/experience <strong>do not</strong> meet the criteria for this question.</p> <p>Information based entirely on the CASE fatality ratio (i.e which ignores the number of unreported infections/asymptomatic infections) is <strong>not</strong> of interest for the purposes of this question for the reasons mentioned.</p> <p>To avoid statistical errors due to small sample sizes, please limit sources to only those findings which are based on populations/sample sizes (total number of infections, either estimated or known) <strong>greater than 500</strong>.</p> <p>Other coronavirus strains already circulating among population before COVID-19 (eg. 229E, HKU1, NL63, OC43) are not of interest for the purposes of this question.</p> <p>In the case of news articles, obviously references should be included in support of data/findings, or at least traceable from the article, otherwise the information is not useful.</p> <p>Goes without saying that the ratio/risk presented in any given source does not, in itself, determine the quality of the answer, and all answers meeting the given criteria are encouraged, regardless how consistent or inconsistent the findings they contain may be with other findings.</p> <p>Feel free to indicate the following data points if they are known when indicating any sources of information, as they are of obvious relevance for the mortality risk (IFR). In any case, I will read all posts and summarize the data under various headings as I have done in my own answer to the question, which I will update as answers come in.</p> <ul> <li>Average age of the people considered in the study, and age stratified mortality risk (mortality risk for different age groups) if known.</li> <li>How much time has passed since all persons considered in the study became infected if known, as deaths can occur after data is collected.</li> <li>Whether Outcome delay adjustments (adding a percentage increase of deaths due to possible deaths after releasing data) are included in the information, if known.</li> <li>Possible underlying illnesses which can increase likelihood of death if known.</li> <li>Other factors.</li> </ul> <p>Below I have provided an answer (now a wiki) where all the sources which I have found or have been provided here meeting the given criteria are summarized with the corresponding mortality risk.</p> <p>Edit (in light of one answer below):</p> <p>Please note, answers based on 'common sense', or which cite or are based on data pertaining to cases (rather than infections) <strong>do not</strong> meet the criteria for this question. For the sake of the clarity and relevance of the data found here, please take the necessary time to research and understand these terms and the criteria specified for the data provided here before posting any data / papers.</p>
9
https://medicalsciences.stackexchange.com/questions/23674/are-there-diseases-for-which-infection-does-not-grant-lasting-immunity-but-a-vac
[ { "answer_id": 23684, "body": "<p>Rabies is almost 100% fatal so there is no chance to develop immunity. So, post-exposure vaccination is used if the person has not been vaccinated prior to exposure.</p>\n\n<blockquote>\n <p>Rabies is a vaccine-preventable, zoonotic, viral disease. Once clinical symptoms appear, rabies is virtually 100% fatal. In up to 99% of cases, domestic dogs are responsible for rabies virus transmission to humans. Yet, rabies can affect both domestic and wild animals. It is spread to people and animals through bites or scratches, usually via saliva.</p>\n</blockquote>\n\n<p><a href=\"https://www.who.int/news-room/fact-sheets/detail/rabies\" rel=\"noreferrer\">https://www.who.int/news-room/fact-sheets/detail/rabies</a></p>\n", "score": 7 }, { "answer_id": 23688, "body": "<p>Varicella zoster - you can get infected and then develop shingles recurrences which are preventable using vaccination eg Shingrix </p>\n\n<p><a href=\"https://www.cdc.gov/vaccines/vpd/shingles/public/shingrix/index.html\" rel=\"noreferrer\">https://www.cdc.gov/vaccines/vpd/shingles/public/shingrix/index.html</a></p>\n", "score": 7 } ]
23,674
CC BY-SA 4.0
Are there diseases for which infection does not grant lasting immunity but a vaccine does?
[ "covid-19", "infection", "immune-system", "vaccination", "disease" ]
<p>There has been a lot of discussion about whether people who have COVID-19 and recover will have long-lasting immunity. At the same time, work is underway to create a vaccine for this disease. But if infection does not necessarily provide immunity, can a vaccine still do it? Are there known diseases for which a vaccine provides durable immunity even when infection does not?</p> <p>I did find <a href="https://www.chop.edu/centers-programs/vaccine-education-center/vaccine-safety/immune-system-and-health" rel="noreferrer">one page</a> that says in passing that "it is true that natural infection almost always causes better immunity than vaccines", but I wasn't able to find anything more detailed about the two types of immunity.</p>
9
https://medicalsciences.stackexchange.com/questions/31109/how-exactly-is-hypoglycemia-a-problem
[ { "answer_id": 31110, "body": "<p>Your tissue gets sugar from the blood (along with the other needed nutrients, and oxygen). Sugar is not stored in places like the brain, brain cells only take up enough sugar for what they need in the short term, because they ordinarily get constant fresh delivery of nutrients and oxygen from blood.</p>\n<p>When you have <a href=\"https://en.wikipedia.org/wiki/Hypoglycemia\" rel=\"noreferrer\">hypoglycemia</a> = low blood sugar, that means there isn't enough sugar available in the blood for tissues to use. It does not mean that the sugar is already in the cells. It's like if you go to the grocery store where you get your food and find they are out of food, it does not mean you have enough food already at home.</p>\n<p>Similarly, the reason that <a href=\"https://en.wikipedia.org/wiki/Hyperglycemia\" rel=\"noreferrer\">hyperglycemia</a> is a problem is not because the blood is keeping it unavailable to cells. Quite the opposite: when there is a lot of sugar in the blood, there's a lot of sugar in the cells, too: too much of it. Sugar in high concentrations is toxic to cells, causing unwanted chemical reactions and <a href=\"https://en.wikipedia.org/wiki/Oxidative_stress\" rel=\"noreferrer\">oxidative stress</a>.</p>\n", "score": 23 } ]
31,109
CC BY-SA 4.0
How exactly is hypoglycemia a problem?
[ "diabetes", "blood-sugar", "hypoglycemia" ]
<p>I am not someone from Medical field. I am asking this question out of curiosity. My question is about sugar levels in blood, particularly low blood sugar (hypoglycemia).</p> <p>I can understand the problem with high blood sugar levels (hyperglycemia) as we want sugar to be in the cells so that it can be used in respiration for generating energy.</p> <p>But I can't quite understand why is hypoglycemia a problem.</p> <p>Google search indicates that dangerously low levels of hypoglycemia can even cause brain death. Does not hypoglycemia mean that sugar is where it should be i.e. in the cells. When sugar is present there in brain cells instead of being in blood, how can it cause brain death as brain cells have enough fuel to burn for powering them?</p> <p>Those stores of energy will only get depleted after some time (should last longer if the person in question is not active enough. Only if one does not replenish these depleted stores, this should be a problem (sort of starvation). But replenishment of stores is quite likely to occur in the meantime. Why is hypoglycemia a big problem then (even regarded more serious than hyperglycemia)?</p> <p>Please enlighten me about this issue. Please forgive me if you found my question silly or naive.</p>
9
https://medicalsciences.stackexchange.com/questions/32139/does-increased-consumption-of-fructose-cause-increased-insulin-resistance-in-hum
[ { "answer_id": 32159, "body": "<h1>TL;DR;</h1>\n<p>Fructose's biochemistry indicates it may lead to increased triglyceride levels in the blood, which can lead to insulin resistance. Data on humans has not yet shown fructose, as a replacement for other simple sugars in the diet, to increase insulin resistance. However, excess fructose has been associated with weight gain and insulin resistance.</p>\n<h1>Biochemistry</h1>\n<h2>Fructose metabolism</h2>\n<p>Glucose and fructose consumed in food first go to the liver by the portal vein. Fructose, unlike glucose, is metabolized almost entirely to intermediates that can eventually lead to glucose production (termed 'gluconeogenesis') or, more commonly, energy and fatty acid production. (1)</p>\n<p>Glucose is primarily stored and metabolized in the liver, adipose (fat) tissue, and skeletal muscle. Increased blood glucose concentrations lead to a peak of insulin secretion after meals, while fructose typically leads to a peak of triglyceride levels in Very Low Density Lipoproteins (VLDLs) produced and secreted in the liver. (2)</p>\n<h2>Insulin resistance</h2>\n<p>Insulin signaling in the cells is rather complicated and not fully understood. Its principal action in glucose metabolism is to cause glucose transporters (GLUT4), that are sequestered in the cytoplasm, to move to cell surface, allowing glucose to enter the cell in high levels.</p>\n<p>Free Fatty Acids (FFAs) and triglycerides (TG) can activate intracellular proteins that deactivate the molecules involved in insulin signaling. Hence, the number of GLUT4 on the membrane does not increase as much, and this is referred to as 'insulin resistance'. (3)</p>\n<p>In conclusion, fructose, on principle, leads to increased circulating FFA and TG, unlike glucose; hence, resistance to insulin's effects may occur in the cells. It has been clinically established that weight gain and increased circulating levels of TG lead to insulin resistance. (4) Whether this is of clinical significance needs to be observed and analyzed in humans.</p>\n<h1>Clinical data</h1>\n<p>An orange typically has fewer than 10 grams of fructose. Estimates on the internet seem to be from 2.4 g to 6 g for an average orange. In a normal diet of 1600 to 2000 Cal, roughly every percent of calorie intake corresponds to 4 g of fructose. 30 g would correspond to 7.5 % of daily calorie intake. Most individuals are unlikely to derive this amount of fructose from consuming fruit during the day. (1)</p>\n<p>The studies on fructose effects on blood markers and weight gain have severe limitations, as mentioned in the respective meta-analyses. The most prominent possible flaws are:</p>\n<ol>\n<li>The duration of follow-up is often two weeks, so longstanding effects remain to be seen. There are some instances of longer, 4- to 10-week follow-up.</li>\n<li>Especially in studies where adverse effects were visible, a high dose of fructose, well beyond normal daily consumption, was used.</li>\n<li>Many studies did not have blinding or were of poor design.</li>\n</ol>\n<ul>\n<li>In diets with the same amount of calories ('isocaloric') where other simple sugars were replaced by fructose, no adverse effects on blood lipids were seen. In diets with 21-35 % excess calories derived from fructose, it did lead to increased lipid biomarkers. (5)</li>\n<li>Fructose effects on weight gain follow a similar pattern. It had no significant effects on weight gain in isocaloric diets, while diets with excess calories dervied mainly from fructose were associated with significant weight gain. (6)</li>\n<li>Sweet beverages sweetened with high-fructose corn syrup (HFCS) were associated with more weight gain than sweet beverages sweetened with glucose, and with higher blood TG levels, after two weeks.</li>\n<li>Diets with varying amounts of HFCS, compared to diets consisting of complex carbohydrates, showed a dose-dependent relationship with increases in weight and blood TG. This suggests that compared to complex carbohydrates, even lower amounts of fructose consumption may lead to weight gain, hence insulin resistance. (1)</li>\n<li>Sweet beverages sweetened with HFCS, compared to glucose, showed higher fat accumulation in the liver and other organs, and less fat accumulation under the skin. The former (visceral fat) is much more detrimental to health than the latter (subcutaneous fat), leading to insulin resistance, fatty liver disease, and vascular lipid abnormalities.(7)</li>\n</ul>\n<hr />\n<sub>\n(1): Herman, M. A., & Samuel, V. T. (2016). The Sweet Path to Metabolic Demise: Fructose and Lipid Synthesis. Trends in endocrinology and metabolism: TEM, 27(10), 719–730. https://doi.org/10.1016/j.tem.2016.06.005<br/>\n(2): Schaefer, E. J., Gleason, J. A., & Dansinger, M. L. (2009). Dietary fructose and glucose differentially affect lipid and glucose homeostasis. The Journal of nutrition, 139(6), 1257S–1262S. https://doi.org/10.3945/jn.108.098186<br/>\n(3): Bhattacharya, S., Dey, D., & Roy, S. S. (2007). Molecular mechanism of insulin resistance. Journal of biosciences, 32(2), 405–413. https://doi.org/10.1007/s12038-007-0038-8<br/>\n(4): Verkouter, I., Noordam, R., le Cessie, S., van Dam, R. M., Lamb, H. J., Rosendaal, F. R., van Heemst, D., & de Mutsert, R. (2019). The Association between Adult Weight Gain and Insulin Resistance at Middle Age: Mediation by Visceral Fat and Liver Fat. Journal of clinical medicine, 8(10), 1559. https://doi.org/10.3390/jcm8101559<br/>\n(5): Chiavaroli, L., de Souza, R. J., Ha, V., Cozma, A. I., Mirrahimi, A., Wang, D. D., Yu, M., Carleton, A. J., Di Buono, M., Jenkins, A. L., Leiter, L. A., Wolever, T. M., Beyene, J., Kendall, C. W., Jenkins, D. J., & Sievenpiper, J. L. (2015). Effect of Fructose on Established Lipid Targets: A Systematic Review and Meta-Analysis of Controlled Feeding Trials. Journal of the American Heart Association, 4(9), e001700. https://doi.org/10.1161/JAHA.114.001700<br/>\n(6): Sievenpiper, J. L., de Souza, R. J., Mirrahimi, A., Yu, M. E., Carleton, A. J., Beyene, J., Chiavaroli, L., Di Buono, M., Jenkins, A. L., Leiter, L. A., Wolever, T. M., Kendall, C. W., & Jenkins, D. J. (2012). Effect of fructose on body weight in controlled feeding trials: a systematic review and meta-analysis. Annals of internal medicine, 156(4), 291–304. https://doi.org/10.7326/0003-4819-156-4-201202210-00007<br/>\n(7): Ma, J., Sloan, M., Fox, C. S., Hoffmann, U., Smith, C. E., Saltzman, E., Rogers, G. T., Jacques, P. F., & McKeown, N. M. (2014). Sugar-sweetened beverage consumption is associated with abdominal fat partitioning in healthy adults. The Journal of nutrition, 144(8), 1283–1290. https://doi.org/10.3945/jn.113.188599\n</sub>\n", "score": 7 } ]
32,139
CC BY-SA 4.0
Does increased consumption of fructose cause increased insulin resistance in humans?
[ "nutrition", "diabetes", "insulin" ]
<p>As far as I understand it, diabetes is a disease that is composed of essentially two issues:</p> <ol> <li>The pancreas' insulin production capabilities</li> <li>The body's sensitivity to insulin</li> </ol> <p>and I'm asking a rather basic question whose answer would seem like common sense to most people, that is:</p> <p>&quot;Does the increased intake of fructose cause increased insulin resistance?&quot;</p> <p>as in, as you increase this specific sugar's intake, does insulin resistance also go up? to determine this, a scientist would have to measure insulin resistance which I certainly have no idea how to do.</p> <p>But assuming it is done, and these two variables are appropriately isolated, what kind of correlations have been found between these two??</p> <p>The background for asking this is that I have known some friends who hopped onto the frugivore fad last year, and their diets are extremely high in sugar from fruit. They still have no sign of diabetes. Although I understand fruits contain many other nutrients and chemicals that may influence insulin resistance, so maybe I should ask</p> <p>&quot;Does high fructose consumption from fruit cause insulin resistance?&quot; in a separate question.</p> <p>this <a href="https://medicalsciences.stackexchange.com/questions/51/is-there-evidence-that-eating-too-much-sugar-can-increase-the-risk-of-diabetes">question</a> is relevant, and I have noted the reviews and studies mentioned by the answer. The thing is, i'm only interested strictly with the statistical and mechanistic relationships between fructose intake and insulin resistance.</p> <p>in the first study linked</p> <blockquote> <p>Consumption of sweet beverages and type 2 diabetes incidence in European adults: results from EPIC-InterAct - Romaguera (and others)</p> </blockquote> <p>it seems they had very few control variables ?</p> <p>they just searched for a correlation between sugary drinks and type 2 diabetes in existing patient records. I speak as a layman but that sounds like very weak evidence, I think a method like this should be strictly used to identify potentially worthwhile directions of study, rather than used as evidence.</p> <p>And in their second source, the journal's review relies rather extensively on rodent studies which i could not be more disinterested in because I have no idea how reliable they are as evidence for humans.</p> <p>But they did mention this old 1980 human study in which a statistical relationship between fructose intake and insulin resistance was found:</p> <blockquote> <p>Impaired cellular insulin binding and insulin sensitivity induced by high fructose feeding in normal subjects</p> </blockquote> <p>but it's an old study, i have not evaluated the methods of measurement they used and they have a sample size of seven people which is much too small though thats not a problem for me as numbers can be corroborated with other studies. Bad study designs are more difficult to corroborate.</p> <p>I understand there's not many studies of the well controlled design i am looking for on this subject, probably due to ethical concerns but whatever there is, please tell me. thank you</p>
9
https://medicalsciences.stackexchange.com/questions/66/what-topical-applications-can-assist-wound-healing-and-prevent-scarring
[ { "answer_id": 273, "body": "<p>It greatly depends on the wound: is it clean or infected? A cut on an abrasion? Acute or chronic. Associated with disease (diabetes), immobility (pressure) or other? Is it a burn?</p>\n\n<p>Honey is often overlooked. It is an antibacterial and a humectant, both helping wounds to heal better. Epidermal growth factor also helps but is not easy to get. Silver is preferred for burns (nanosilver is making an appearance). Collagen gels and other topicals are helpful. The body of literature is huge.</p>\n\n<p>I like an ointment with lanolin and allantoin, both of which promote healing.</p>\n\n<p><sub><a href=\"http://journals.lww.com/jwocnonline/Abstract/2002/11000/Honey__A_Potent_Agent_for_Wound_Healing_.8.aspx\">Honey: A Potent Agent for Wound Healing?</a></sub><br>\n<sub><a href=\"http://onlinelibrary.wiley.com/doi/10.1002/jps.21210/full\">Wound healing dressings and drug delivery systems: A review</a></sub><br>\n<sub><a href=\"http://www.sciencedirect.com/science/article/pii/S0190962206008279\">Topical treatments for hypertrophic scars</a></sub><br>\n<sub><a href=\"http://www.biomedcentral.com/1472-6882/1/2\">Systematic review of the use of honey as a wound dressing</a></sub></p>\n", "score": 6 } ]
66
CC BY-SA 3.0
What topical applications can assist wound healing and prevent scarring?
[ "wound", "wound-care" ]
<p>I have used vitamin E to help prevent scarring. Are there any other topical applications that can assist wound healing and prevent scarring?</p>
8
https://medicalsciences.stackexchange.com/questions/74/how-safe-are-backboards
[ { "answer_id": 107, "body": "<p>The only studies I'm aware of come from the Emergency Medicine Journal, but other should exist for sure.</p>\n\n<p>Some say it has drawbacks (discomfort, pressure sore) and that alternatives such as the vacuum mattress should be preferred:</p>\n\n<ul>\n<li><a href=\"http://emj.bmj.com/content/20/5/476.abstract\" rel=\"nofollow\">Comparison of a long spinal board and vacuum mattress for spinal immobilisation</a></li>\n<li><a href=\"http://emj.bmj.com/content/18/1/51.abstract\" rel=\"nofollow\">The use of the spinal board after the pre-hospital phase of trauma management</a></li>\n</ul>\n\n<p>However, according to official guidelines (such as <a href=\"http://www.interieur.gouv.fr/Le-ministere/Securite-civile/Documentation-technique/Le-secourisme/Les-textes-reglementaires\" rel=\"nofollow\">PSE1 and PSE2</a> that we apply here in France and that follow international guidelines), each tool has its proper use cases. For example (non-exhaustive list):</p>\n\n<ul>\n<li>The vacuum mattress is used in case of suspected trauma of the\n<ul>\n<li>head</li>\n<li>spine (lying victim)</li>\n<li>pelvis</li>\n<li>femur</li>\n<li>and for multiple traumas.</li>\n<li>It is carried on a stretcher or a spinal board, once the victim installed.</li>\n</ul></li>\n<li>while the spinal board is used for\n<ul>\n<li>single traumas not listed above and preventing the victime from moving </li>\n<li>spine trauma of a sitting or standing vitim, in conjunction with other tools</li>\n<li>drawning </li>\n<li>carrying the vacuum mattress (see above)</li>\n<li>a few more cases not listed here. </li>\n<li>And the spinal board allows doing CPR, while the vacuum mattress doesn't.</li>\n</ul></li>\n</ul>\n\n<p>Respecting these use cases is the best way to reduce the risk for the victim, according to the professionals who wrote these international guidelines. This may evolve in the future or not, depending on studies and feedback, but currently, this is the standard.</p>\n\n<p>And finally, as the spinal board is used in a context of first-aid, the victim is not immobilized on it for a long time: just the time to provide first aid and to evacuate to the hospital. I have personnaly never seen (nor heard about) any pressure sore or anything like that appearing after a spinal board immobilization. But it is true this board is not comfortable at all (I tried).</p>\n", "score": 6 } ]
74
CC BY-SA 3.0
How safe are backboards?
[ "emergency", "first-aid", "spine" ]
<p>I have heard a fair amount of talk recently about how safe the long spine boards frequently used by EMS personnel after falls and car accidents are. How many - if any - studies have been done on this?</p> <p>If there have been studies done on this I would like to know what the conclusion was. What are the chances of having damage done by being on one for any length of time?</p> <p>This link to <a href="http://www.emsworld.com/article/10964204/prehospital-spinal-immobilization" rel="noreferrer">EMS World</a> is where I got the information about the possible safety issues. </p>
8
https://medicalsciences.stackexchange.com/questions/125/is-eye-patching-effective-for-older-children-with-amblyopia
[ { "answer_id": 177, "body": "<p>Some studies have shown that eye patching has been effective in adults. One study<a href=\"http://www.lazyeye.org/lazy-eye-amblyopia-age-treatment-adult.html\" rel=\"nofollow\"><sup>1</sup></a> tested teenagers ages 13-17 and found that, combined with glasses and near vision activity, patching was effective in treating lazy eye. In fact there have been studies on treatment of amblyopia in older children/adults as early as 1957<a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2764839/#R44\" rel=\"nofollow\"><sup>2</sup></a>, but this study was only performed on seven cases of amblyopia, so while it did show that patching combined with vision therapy did help treat amblyopia. Luckily, scientists have developed other ways to treat it, such as playing Tetris.<a href=\"http://www.news-medical.net/health/New-hope-for-adults-with-amblyopia.aspx\" rel=\"nofollow\"><sup>3</sup></a></p>\n\n<hr>\n\n<p><sup>[<a href=\"http://www.lazyeye.org/lazy-eye-amblyopia-age-treatment-adult.html\" rel=\"nofollow\">1</a>] <a href=\"http://www.lazyeye.org/lazy-eye-amblyopia-age-treatment-adult.html\" rel=\"nofollow\">Successful Improvement of Eyesight with Therapy for Patients with Lazy Eye Proven Possible at Later Ages by Many New Scientific Studies</a></sup></p>\n\n<p><sup>[<a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2764839/#R44\" rel=\"nofollow\">2</a>] <a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2764839/#R44\" rel=\"nofollow\">Treatment of amblyopia exanopsia in adults; a preliminary report of seven cases</a></sup></p>\n\n<p><sup>[<a href=\"http://www.news-medical.net/health/New-hope-for-adults-with-amblyopia.aspx\" rel=\"nofollow\">3</a>] <a href=\"http://www.news-medical.net/health/New-hope-for-adults-with-amblyopia.aspx\" rel=\"nofollow\">New hope for adults with amblyopia (lazy eye)</a></sup></p>\n", "score": 5 } ]
125
CC BY-SA 3.0
Is eye patching effective for older children with amblyopia?
[ "optometry" ]
<p>Parents of young children with amblyopia are often advised that vision in the weak eye can be improved by covering the healthy eye with an eye patch for a couple of hours every day. At what age does eye patching become less effective? Does the age at which the patching began matter?</p>
8
https://medicalsciences.stackexchange.com/questions/154/are-dairy-products-effective-sources-of-calcium
[ { "answer_id": 200, "body": "<p>Dairy products are not the best source of calcium for many reasons.</p>\n\n<ul>\n<li><h3>Lactose Intolerance</h3>\n\n<ul>\n<li>Lactose intolerant people can't have dairy products as they will usually cause various symptoms like diarrhea or cramping</li>\n</ul></li>\n<li><h3>High Saturated Fat Content</h3>\n\n<ul>\n<li>Most dairy products are high in saturated fat, which can be a risk factor for heart disease</li>\n<li>Milk has been able to cut down on this with reduced fat and fat-free options, but other dairy products, like cheese and ice cream are still very high in fat</li>\n</ul></li>\n<li><h3>Cancer Risk</h3>\n\n<ul>\n<li><p>Ovarian Cancer - Studies have shown that high intakes of lactose (equal to 2-3 servings of milk) can increase the risk of ovarian cancer<sup>1</sup></p></li>\n<li><p>Prostate Cancer - Studies showed inconclusive evidence that some men with a higher calcium intake might have a higher risk of prostate cancer; <strong>Evidence was not conclusive</strong>; Could also be linked to just calcium rather than dairy products<sup>2</sup></p></li>\n</ul></li>\n</ul>\n\n<p>Though dairy products are a convenient source, and they are high in protein and vitamins A and D, they are not the best source for calcium. In small amounts, dairy is fine, but there are good alternative sources.</p>\n\n<h3>Other sources</h3>\n\n<ul>\n<li>Leafy green vegetables - kale, spinach, lettuce</li>\n<li>Beans, legumes, and almonds</li>\n<li>Calcium supplements</li>\n</ul>\n\n<hr>\n\n<p><sub>[1] <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/16492930?dopt=Citation\" rel=\"noreferrer\">Dairy products and ovarian cancer</a></sub></p>\n\n<p><sub>[2] <a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2360740/\" rel=\"noreferrer\">Dairy products, calcium and prostate cancer risk\n</a></sub></p>\n\n<p><sub><a href=\"http://www.hsph.harvard.edu/nutritionsource/calcium-full-story/#calcium-from-milk\" rel=\"noreferrer\">Should You Get Calcium from Milk?</a></sub></p>\n", "score": 7 }, { "answer_id": 401, "body": "<p>The issue whether “excess” dietary protein intake adversely affects bone in humans is a subject of current controversy in nutrition<sup>(1),(2),(3)</sup> with one group concluding that “excess protein will not harm the skeleton if the calcium intake is adequate”<sup>(3)</sup> and group that “excessive dietary protein from foods with high potential renal acid load (e.g., animal foods) adversely affects bone, unless buffered by the consumption of alkali-rich foods (e.g. vegetable foods)”<sup>(1)</sup> (quoted by Frassetto 2000).</p>\n\n<p>Other studies reporting better bone health in women with greater protein intakes<sup>(4),(5)</sup> (high protein intake prevents BMD decrease). Further, the Munger study reported that higher intakes of animal sources of dietary protein were associated with a 70% reduction in hip fracture, even after controlling for major confounding variables (Hannan 2000).</p>\n\n<p>Read more: <a href=\"https://scienceandveganism.wordpress.com/topics/calcium-bmd-osteoporosis/\" rel=\"nofollow\">Calcium, BMD and Osteoporosis</a></p>\n\n<p>In overall it's difficult to say whether calcium intake has positive or negative effect from the consumption of dairy products on our bones, based on the sample size and subject characteristics of the studies, so more studies needs to be conducted.</p>\n\n<hr>\n\n<p>References:</p>\n\n<ol>\n<li>Barzel US, Massey LK. Excess dietary protein can adversely affect bone. J Nutr. 1998;128:1051–1053.</li>\n<li>Massey LK. Does excess dietary protein adversely affect bone? Symposium overview. J Nutr. 1998;128:1048–1050.</li>\n<li>Heaney RP. Excess dietary protein may not adversely affect bone. J Nutr. 1998;128:1054–1057.</li>\n<li>Freudenheim et al.(46, Freudenheim JL, Johnson NE, Smith EL 1986</li>\n<li>47, Munger Cerhan JR, Chiu BC 1999 Prospective study of dietary protein intake and risk of hip fracture in postmenopausal women.</li>\n</ol>\n", "score": 5 }, { "answer_id": 13747, "body": "<p>First of all, I'm not sure whether the question is answerable at all without a more detailed scenario.</p>\n\n<p>So we have:</p>\n\n<ul>\n<li><p>Ca²⁺ excretion increasing with excess protein<br>\nThis seems to be linked to elimination of excess acids rather than directly to protein according to <a href=\"http://jn.nutrition.org/content/141/3/391.long\" rel=\"nofollow noreferrer\">http://jn.nutrition.org/content/141/3/391.long</a>.<br>\n <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/15546911\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pubmed/15546911</a> finds the additional excretion coming from the increased intake under high protein diet.</p></li>\n<li><p>Ca²⁺ uptake/loss in bones (which is typically the main point of the Ca uptake/loss discussion, and bone is a large researvoir of Ca in the human body):<br>\nbone (re)building needs:</p>\n\n<ul>\n<li>Ca²⁺</li>\n<li>protein<br>\n(we're talking here high/excess protein diets, so let's assume this is not a limiting factor) </li>\n<li>mechanical stimulation (excercise)</li>\n</ul></li>\n<li><p>if you are in a situation with (primarily) net loss of bone because of <em>any</em> of the 3 ingredients to bone growth above (e.g. lack of excercise even though Ca and protein are available), you'll observe a net Ca loss, because Ca released from the bone that (naturally) broken down is excreted.</p></li>\n<li><p>Ca²⁺ uptake from food depends on</p>\n\n<ul>\n<li>bioavailablility, which depends on presence/absence of other substances.</li>\n<li>e.g. oxalate will precipitate Ca as insoluble and bioinavailable Ca-oxalate (in 1:1 mol ratio). </li>\n<li>there are studies indicating that high-protein food increases Ca uptake, see e.g. <a href=\"http://jn.nutrition.org/content/141/3/391.long\" rel=\"nofollow noreferrer\">http://jn.nutrition.org/content/141/3/391.long</a> </li>\n<li><p>vitamin D status of the recipient: vitamin D is needed to transport Ca²⁺, and <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/24335055\" rel=\"nofollow noreferrer\">roughly, the higher the vitamin D level, the higher the Ca uptake</a><br>\nNot only rachitis in children but also osteoporosis in old people is correlated with vitamin D deficiency. </p></li>\n<li><p><a href=\"http://ajcn.nutrition.org/content/75/4/609.full\" rel=\"nofollow noreferrer\">http://ajcn.nutrition.org/content/75/4/609.full</a> outlines a mechanism how urinary Ca loss may trigger increased Ca uptake.</p></li>\n</ul></li>\n</ul>\n\n<p>Taking those points together, we may construct 2 extreme lifestyles that would react quite opposite to the linked intake of protein + calcium in milk: </p>\n\n<ul>\n<li><p>On the one hand, imagine a sedentary indoors couch potato. No sun (low vitamin D), no excercise (no bone growth stimulus). Without adequate vitamin D levels, the Ca in the milk (although in principle bioavailable) is not even absorbed in the gut. Even if it were (or: even the little that is) is not used for net new bone growth as the excercise stimulus is missing. With a high protein diet (or, a diet causing excess acid urinary excretion), Ca is lost. It may have been lost even without a high protein diet because of bone loss due to lack of excercise. Or, with a low excess acid diet, bone would have been maintained even with the low level of excercise. </p></li>\n<li><p>On the other hand, consider a physically active outdoors person. Excercise gives a bone growth stimulus, sunlight does its share in supplying vitamin D. In that scenario, milk gives the protein as well as the Ca to actually grow bone. Result is a net gain in Ca, even though some Ca is excreted via urine.</p></li>\n</ul>\n\n<p><em>Slightly off topic: this whole scenario feels a bit like a 101 in how to lie with statistics without actually lying: we have at least 4-5 factors that need to be at the right setting (and for 4 of them it is comparatively easy to be off) in order to achieve bone growth/net Ca gain. Now any study looking at a single factor will not find an effect unless they make sure all other factors are right. And if one factor is worse with the treatment group than the controls, a study may even seem to observe the opposite of what is really going on.</em></p>\n\n<hr>\n\n<p>I tried to find numbers for Ca²⁺ excretion per gram of protein. A rough guesstimate based on <a href=\"http://jn.nutrition.org/content/128/6/1051.full\" rel=\"nofollow noreferrer\">http://jn.nutrition.org/content/128/6/1051.full</a> would be up to 200 mg Ca²⁺ urinary excretion for 150 g of protein consumption. Based on that rough guesstimate, food with a ratio > 1.33 mg Ca/g of protein would be considered as \"gaining Ca²⁺\". </p>\n\n<p><a href=\"https://en.wikipedia.org/wiki/Milk#Nutrition_and_health\" rel=\"nofollow noreferrer\">https://en.wikipedia.org/wiki/Milk#Nutrition_and_health</a> gives cow milk with 30 - 35 g protein / l and 1200 mg Ca²⁺/l, yielding a Ca : protein ratio of > 30 mg Ca/g of protein. Even assuming just the average absorption rate for Ca in food of 30 % (<a href=\"http://ajcn.nutrition.org/content/35/4/783.extract\" rel=\"nofollow noreferrer\">http://ajcn.nutrition.org/content/35/4/783.extract</a> - didn't find numbers for milk, though it is frequently cited as highly bioavailable - but then it will also depend on other factors) that leaves almost an order of magnitude to the side of more Ca uptake than increase in excretion. </p>\n\n<p>So overall, this <strong>back-of-the-envelope calculation is in favor of milk being a net source of Ca</strong>. Note however, that not all dairy products have the same Ca:protein ratio as milk. E.g. <a href=\"https://en.wikipedia.org/wiki/Whey\" rel=\"nofollow noreferrer\">Whey</a> has even more Ca:protein, and consequently the cheese of which whey is a leftover/side product has a somewhat lower Ca:protein ratio. </p>\n", "score": 2 } ]
154
CC BY-SA 3.0
Are dairy products effective sources of calcium?
[ "nutrition", "dairy", "calcium" ]
<p>Tradition says that dairy products are good sources of calcium just because they have it; while some modern studies (see below) show that protein digestion produces acidic environment, and body uses calcium from the bones to re-establish the correct pH. These opinions say that dairy products could even be detrimental to bone density and osteoporosis.</p> <p>So in the end calcium balance is positive or negative from the consumption of dairy products?</p> <p><em>References</em></p> <h2>Protein metabolism and calcium loss</h2> <p>It was asked in the comments to provide some reference about the "modern studies" relating calcium loss to protein intake.</p> <blockquote> <p>The specific amino acid profile—especially of amino acids containing sulfur—determines the calciuretic effect of protein. Sulfate generated from the metabolism of these amino acids increases the acidity of the urine, causing greater amounts of calcium to be excreted in the urine. The proteins of many plants, especially legumes, have lower amounts of methionine and cysteine than do animal proteins.</p> </blockquote> <p><em>Weaver, C. M., Proulx, W. R., &amp; Heaney, R. (1999). <a href="http://www.ncbi.nlm.nih.gov/pubmed/10479229" rel="nofollow">Choices for achieving adequate dietary calcium with a vegetarian diet</a>. The American Journal of Clinical Nutrition, 70(3 Suppl), 543S–548S</em></p> <blockquote> <p>To date, the accumulated data indicate that the adverse effect of protein, in particular animal (but not vegetable) protein, might outweigh the positive effect of calcium intake on calcium balance.</p> </blockquote> <p><em>Amine et al. (2002). <a href="http://dro.deakin.edu.au/view/DU:30010488" rel="nofollow">Diet, nutrition and the prevention of chronic diseases: report of a Joint WHO/FAO Expert Consultation.</a></em></p>
8
https://medicalsciences.stackexchange.com/questions/191/right-wrist-pain-from-using-computer-mouse
[ { "answer_id": 197, "body": "<p>After experimenting different motions with my mouse for some while, I'm now certain it has to do with the effort spent in mouse-movement.</p>\n\n<p>I feel that it's the hand-movement that causes the pain rather than the clicks.<br>\nAnyway my system (Win8.1) is configured with max speed, but I believe this already fits in <a href=\"https://superuser.com/questions/211410/increase-mouse-pointer-speed\" title=\"Increase mouse pointer speed\">another scope</a>.</p>\n\n<p>Which led me to the following conclusions about the mouse environment, which I'm sure when addressed, will solve my hand-pain issues.</p>\n\n<ul>\n<li>Wired mouse (as opposed to wireless) not only slows down the mouse but also restrains the mouse and forces the hand with having to extra-pull the mouse</li>\n<li>A smooth and clean mouse pad - to avoid mouse obstacles and smooth moving of it</li>\n<li>A clean mouse bottom</li>\n<li>A light mouse</li>\n<li>Led of mouse that responds very efficiently</li>\n</ul>\n\n<p>I wish there would be a hovering mouse. That would surely solve lots of problems.</p>\n\n<p>Will keep on updating after I fix up my environment. It might take a while until I go shopping but I sure will update once I have news.</p>\n\n<p><strong>UPDATE</strong></p>\n\n<p>As some suggested here, I started using the mouse with my left hand, which is also a great solution. Indeed a big challenge at first, but the advantages are not only health and no-pain, but I think it also develops the sensitivity of the left hand, wrist and fingers.</p>\n", "score": 3 }, { "answer_id": 236, "body": "<p>The image you drew to image the pain is almost perfectly aligned with your wrist muscles, specifically: <a href=\"http://www.coursesmart.com/clinical-kinesiology-and-anatomy-5th-edition/lippert-lynn/dp/9780803626324\" rel=\"nofollow noreferrer\"><sup>Book</sup></a></p>\n<ul>\n<li>Extensor Carpi Radialis Longus</li>\n<li>Extensor Carpi Radialis Brevis</li>\n<li>Extensor Carpi Ulnaris</li>\n</ul>\n<p>Do you feel the pain on the palm <em>(anterior)</em> side too?\nThe above muscles work with: <a href=\"http://www.coursesmart.com/clinical-kinesiology-and-anatomy-5th-edition/lippert-lynn/dp/9780803626324\" rel=\"nofollow noreferrer\"><sup>Book</sup></a></p>\n<ul>\n<li>Flexor Carpi Radialis</li>\n<li>Flexor Carpi Ulnaris</li>\n</ul>\n<p>to create a ulnar <em>(towards pinky)</em> and radial <em>(towards thumb)</em> deviation <em>(movement)</em> of the wrist</p>\n<p>If during your 5-18 hour's daily you make extensive use of the mouse, wrist pain makes sense.\nThe best thing to do is to rest the hand from making these movements which means stop using the mouse.</p>\n<p>You say you use Windows, but if you are dealing heavily with text I would actually suggest using Vi or Vim. Vi is designed around not using the mouse and using keyboard shortcuts for everything. I'm fairly sure Vi is available for windows <sup><a href=\"https://duckduckgo.com/?q=Vi+for+windows&amp;t=lm\" rel=\"nofollow noreferrer\">Search</a></sup></p>\n", "score": 3 }, { "answer_id": 949, "body": "<p>I have suffered acutely from this phenomenon, and tried every single item in the list given in the accepted answer (as well as many others).</p>\n\n<p>The most important thing I found is separating the click from the move. So one hand moves and the other clicks.</p>\n\n<p>I've mapped the \"Fn\" key on the bottom left of my Apple wireless keyboard to the left mouse button using \"Karabiner\".</p>\n\n<p>I use a gel mousepad and hold the mouse between the thumb and third finger.</p>\n\n<p>What I have noticed is that typical mouse movement requires you to clamp the position of the mouse while you click, so that it doesn't move even by one pixel.</p>\n\n<p>If you observe children attempting to use the mouse, you'll see that initially they have difficulty clicking, the click smears and turns into a drag. If you try using the mouse with your other hand, you will become aware of this.</p>\n\n<p>And I think it is the movement of a tendon through the wrist and arm in this state of tension that causes the pain.</p>\n\n<p>Previously I have used a footpedal to perform the click. I rigged it up so that it is beneath my heel, and lifting creates the mouse-down. So that the foot is naturally in a relaxed position. Initially I was using this together with a head-pointing device, but as my health improved the path of least resistance returned (over several years) to being a conventional mouse.</p>\n\n<p>Also alternating hands for the mouse is a good idea. Train yourself to use both hands.</p>\n\n<p>Using speech recognition is essential also to take load off the hands. I wouldn't be able to function without it now. On OS X this is now excellent -- I don't even need an external microphone.</p>\n\n<p>Additionally I have got myself a standing workspace. I'm currently working on workspace that supports both standing and sitting.</p>\n", "score": 2 }, { "answer_id": 3691, "body": "<p>I have a very easy solution that will work great for you. I had similar problem. I was developing potentially impairing carpal tunnel syndrome on my right hand. I simply taught myself to use the mouse with my left hand. It is actually really easy. You really do not need to be ambidextrous. Within 5 to 10 minutes, you probably will forget you are using the mouse with your non-dominant hand. As you do that, your problems will go away with your right hand. You may notice over time that those problems may surface on the other hand. And, when that occurs you simply shift back to the other hand until the left hand is rested. And, then shift back again. </p>\n\n<p>I also have maintained a regime whereby I use my left hand at work, where I do most of my mousing. But, when I am home I shift back to my right hand. I have done that successfully for years with no more major issues on either side. You may try a version of this. </p>\n", "score": 2 } ]
191
Right wrist pain from using computer mouse
[ "computers", "pain", "hand", "wrist" ]
<p>I'm Shimmy, almost 30ish, Male, 6', 158 lbs.</p> <p>I'm a heavy computer user and sit in front of my homedesk for long intervals (5-18h daily).</p> <p>I use the computer mostly for working with text (software development), selecting text, accessing menus, drag-drop etc.</p> <p>In seasons, depending on how heavily I'm sitting at my desk, I suffer from right hand strain and pain.</p> <p>It might be due the wrong chair height or desk setup, wrong sitting, hand rest or whatever. Please help me find out what's causing the problem, what does this kind of pain signal, and what can I do to avoid it and any related injury. </p> <p>I suspect it might be because of the hand-rest, is it related? If yes, should I rest/unrest my hand on it? Should I completely remove it? Should I lift my chair a bit? Any other mouse set ups and other alternatives to consider?</p> <p><img src="https://i.stack.imgur.com/BcZxt.png" alt="enter image description here"><br> In the preceding figure, I tried to mark on this picture the channels I feel pain, but the most of it is either at the wrist knuckle (between arm and hand), and at my hand top.</p> <p>I use the <a href="http://tzora-global.com/%D7%A8%D7%99%D7%90%D7%9C%D7%98%D7%95" rel="noreferrer">Tzora Rialto</a> chair, not that I believe anyone knows, but it's a pretty customizable chair, I just don't know to choose the right setup (you can see the available customizations in their website, see the middle tab on the bottom):<br> <a href="https://i.stack.imgur.com/7OYRc.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/nVNOKt.jpg" alt="enter image description here" title="Click to enlarge chair"></a></p> <p>Here're some pictures of my desk setup and my hand as I normally sit on it:</p> <p><a href="https://i.stack.imgur.com/uhYp4.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/uhYp4t.jpg" alt="enter image description here" title="Click to open"></a> <a href="https://i.stack.imgur.com/4h2b9.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/4h2b9t.jpg" alt="enter image description here" title="Click to open"></a> <a href="https://i.stack.imgur.com/dhzQ9.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/dhzQ9t.jpg" alt="enter image description here" title="Click to open"></a></p>
8
https://medicalsciences.stackexchange.com/questions/218/outcomes-and-risks-of-lasik-surgery
[ { "answer_id": 222, "body": "<p>Post-operative complications include the following:</p>\n\n<ul>\n<li>Visually significant wrinkles or striae in the flap (1%)</li>\n<li>Dislocated flap (early postoperative period)</li>\n<li>Infection (early postoperative period; very rare; &lt; 0.02%)</li>\n<li>Diffuse intralamellar keratitis (&lt; 0.1%)</li>\n<li>Epithelial ingrowth (early to late postoperative; 1-2%)</li>\n<li>Under/overcorrection (see results)</li>\n<li>Ectasia (incidence unknown; &lt; 0.01%)</li>\n</ul>\n\n<p>In general, LASIK results are better for patients with low myopia (between 1-6 D) and low astigmatism (&lt; 1 D). Stability has been reported to be good with little or no change noted in most patients between 3 months and 1 year postoperative. Other factors that can affect results include the type of laser and microkeratome used and surgeon experience.</p>\n\n<p>But:</p>\n\n<ol>\n<li>But personally I have heard from some of my colleges that it can recur again after 10yr or so.</li>\n<li>The procedure is nothing but to reduce cornea part of eye, so in future at old age if you develop cataract (which has incidence of above 70%among old age people), cataract surgery options gets limited because we have lost considerable amount of cornea for this LASIK. </li>\n<li>My old Opthalmology professor, denied me to go for LASIK (I am too myopic - wear glass). He gave me 5 min lecture on that day telling about complication (I miss him now though). This conversation happened 2 yr back. Not ages old.</li>\n<li>He just told \"don't waste your cornea\" </li>\n</ol>\n", "score": 5 }, { "answer_id": 377, "body": "<p>Risks of LASIK (Laser-Assisted in situ Keratomileusis) can include:</p>\n\n<p><ul>\n<li><p><a href=\"http://www.webmd.com/eye-health/news/20061010/lasik-surgery-safer-than-contacts\" rel=\"nofollow\">Vision loss due to infection</a>,</p></p>\n\n<blockquote>\n <p>The researchers calculated the risk of significant vision loss consequence of LASIK surgery to be closer to 1-in-10,000 cases.</p>\n</blockquote></li>\n<li><p>Higher-order aberrations,</p>\n\n<blockquote>\n <p>These aberrations include 'starbursts', 'ghosting', 'halos' and others.</p>\n</blockquote></li>\n<li><p>Dry eyes,</p>\n\n<blockquote>\n <p>Although it is usually temporary it can develop into <a href=\"http://en.wikipedia.org/wiki/Keratoconjunctivitis_sicca\" rel=\"nofollow\">dry eye syndrome</a>.</p>\n</blockquote></li>\n<li><p>Halos,</p>\n\n<blockquote>\n <p>Some post-LASIK patients see halos and starbursts around bright lights at night.</p>\n</blockquote></li>\n<li><p>Other complications include:</p>\n\n<p><ul>\n<li>flap complications (0.244%),</li>\n<li>\"slipped flap\",</li>\n<li>\"Flap interface particles\",</li>\n<li><a href=\"http://en.wikipedia.org/wiki/Diffuse_lamellar_keratitis\" rel=\"nofollow\">Diffuse lamellar keratitis (or DLK)</a>,</li>\n<li>Infection (0.4%),</li>\n<li><a href=\"http://en.wikipedia.org/wiki/Post-LASIK_ectasia\" rel=\"nofollow\">Post-LASIK corneal ectasia</a> (similar to keratoconus),</li>\n<li>subconjunctival hemorrhage (10.5%),</li>\n<li>Corneal scarring,</li>\n<li>epithelial ingrowth (0.1%)</li>\n<li>traumatic flap dislocations,</li>\n<li><a href=\"http://en.wikipedia.org/wiki/Glaucoma\" rel=\"nofollow\">Glaucoma</a>,</li>\n<li><a href=\"http://en.wikipedia.org/wiki/Retinal_detachment\" rel=\"nofollow\">Retinal detachment</a> (0.36%),</li>\n<li><a href=\"http://en.wikipedia.org/wiki/Choroidal_neovascularization\" rel=\"nofollow\">Choroidal neovascularization</a> (0.33%),</li>\n<li><a href=\"http://en.wikipedia.org/wiki/Uveitis\" rel=\"nofollow\">Uveitis</a> (0.18%),</li>\n<li><a href=\"http://en.wikipedia.org/wiki/Corneal_keratocyte\" rel=\"nofollow\">corneal keratocytes</a></li>\n<li>Late postoperative complications</p>\n\n<blockquote>\n <p>A large body of evidence on the chances of long-term complications is not yet established and may be changing due to advances in operator experience, instruments and techniques.</li>\n </ul></p>\n</blockquote></li>\n</ul>\n\n<blockquote>\n <p>Some people with poor outcomes from LASIK surgical procedures report a significantly reduced quality of life because of vision problems or physical pain associated with the surgery. A small percentage of patients may need to have another surgery because their condition is over-corrected or under-corrected.</p>\n</blockquote>\n\n<p>Source: <a href=\"http://en.wikipedia.org/wiki/LASIK#Risks\" rel=\"nofollow\">LASIK - Risks</a> at Wikipedia</p>\n", "score": 1 } ]
218
CC BY-SA 3.0
Outcomes and risks of LASIK surgery
[ "side-effects", "eye", "surgery", "ophthalmology", "lasik" ]
<p>If an individual with poor eyesight undergoes LASIK surgery, will it return the sight exactly to normal? What are the risks of the procedure? Are there any side effects or complications to be concerned about?</p>
8
https://medicalsciences.stackexchange.com/questions/248/do-benadryl-and-loratadine-contain-the-same-active-ingredient
[ { "answer_id": 250, "body": "<p>No, they do not contain the same active ingredient. Benadryl (trade name) is also known as <a href=\"http://en.wikipedia.org/wiki/Diphenhydramine\">diphenhydramine</a> (generic name); <a href=\"http://en.wikipedia.org/wiki/Loratadine\">loratidine</a> (generic name) is also known as Claritin (trade name). Both drugs are primarily antihistamines and primarily active antagonists at the H1 subtype of histamine receptor. It is this property that makes them effective for treatment of allergies. </p>\n\n<p>The difference between the two medications is that <a href=\"http://en.wikipedia.org/wiki/Diphenhydramine\">diphenhydramine</a> is a first generation or “non-selective” antihistamine. The term “non-selective” refers to these drugs' activity at a variety of receptors other than H1 - primarily, acetylcholine receptors. This can lead to more anticholinergic side effects such as dry mouth, urinary retention, etc. First generation antihistamines are also highly <a href=\"http://en.wikipedia.org/wiki/Lipophilicity\">lipophilic</a>, which means they cross the blood-brain barrier and have central nervous system activity. It is this property which makes them quite sedating (primarily due to activity at CNS histamine receptors).</p>\n\n<p>Second generation antihistamines were designed to avoid some of the side effects of first generation agents. They are more specific for the H1 receptor and are mostly <a href=\"http://en.wikipedia.org/wiki/Lipophobicity\">lipophobic</a>, meaning they poorly penetrate the blood-brain barrier, resulting in fewer CNS effects. For more information about antihistamines, this <a href=\"http://www.ncbi.nlm.nih.gov/books/NBK50558/\">Drug Class Review</a> is quite informative. </p>\n\n<p><strong>Is one better than the other for hay fever?</strong> </p>\n\n<p>Probably not. It’s just a matter of dose that determines how much anti-histamine activity each provides. The trouble is that many people will find the side effects of diphenhydramine and other non-selective agents to be dose-limiting, in which case practically it may not be as effective.</p>\n\n<p><strong>Should they be taken together (staggered or otherwise)?</strong></p>\n\n<p>I see no clear benefit to this. Again, their activity against hay fever is mediated by the same receptor. As such, they will just have additive effects. Taking twice as much of one or the other would similarly increase activity against hay fever and/or to contribute to untoward side effects. So it’s “OK” to take them together in the same way that it’s “OK” to take twice as much of either one. </p>\n\n<p>In general, I see little reason to use diphenhydramine for allergic indications unless there is a desire for the sedative properties. Loratadine and other second generation agents have overtaken it in usefulness in this area.</p>\n", "score": 13 } ]
248
CC BY-SA 3.0
Do Benadryl and Loratadine contain the same active ingredient?
[ "allergy", "drug-interactions", "overdose", "antihistamines", "hay-fever" ]
<p>When I get bad Hay Fever, I take either Benadryl or Loratadine. I am wondering what the active ingredients are in these, and Is it okay to take them both together (or would that be over dosing)?</p> <p>On top of that, is there any <em>benefit</em> to taking them both at once - should I stagger them or just take one or the other - whichever works best for me?</p>
8
https://medicalsciences.stackexchange.com/questions/382/what-should-my-daily-intake-of-calories-be
[ { "answer_id": 389, "body": "<p>As an approximation, there exist several different equations for calculating a basal/resting metabolic rate. These are:</p>\n\n<ul>\n<li>Harris-Benedict</li>\n<li>Harris-Benedict revised</li>\n<li>Cunningham</li>\n<li>Katch-McCardle</li>\n<li>Mifflin St. Jeor</li>\n</ul>\n\n<p>Each of these takes various factors such as age, lean body mass, sex into account in varying emphases to come up with a basal, or resting metabolic rate. This rate is basically how many calories you would need on a daily basis to simply breathe in and out all day long. If you run through all of them and then average, you should come pretty close to your basic needs. There are many calculators already programmed on the internet with these formulas, or you can get them <a href=\"http://en.wikipedia.org/wiki/Basal_metabolic_rate\">here at the wiki link</a>.</p>\n\n<p>Once you have that, then you can take a look at the various sites on the internet that have calorie expenditures for various activities such as housework, office work, weightlifting, running, really just about any activity. Most of these are again approximations, the best charts will account for height/weight/age/sex. Add those to your BMR, and you should be pretty close to a daily intake need.</p>\n\n<p>Really, though, all you need to do is track your weight. Take note of any long term trends on the scale, and if you are gaining weight, cut back on calorie intake or food makeup (healthier vs. unhealthy). If you are losing too much weight, eat more. Don't be alarmed by daily fluctuations, you can vary quite a bit during a day. Best bet is to weigh yourself under the same conditions daily.</p>\n\n<p>If you are lucky enough to have a college lab or similar that supports general testing for the public (You can occasionally get in on a kinesiology class testing phase where they need subjects), you can get exhaled gas analysis, and this can give you a very close estimate of calories burned during a specific activity. This is somewhat rare and/or costly to have done.</p>\n", "score": 7 }, { "answer_id": 391, "body": "<p>JohnP has already given the right answer for it, but here is a quick solution if you are not so much into all those calculations.</p>\n\n<blockquote>\n <p>Amount of calories you should take everyday = Basal metabolic Rate\n over 24 hours X Physical Activity Level</p>\n</blockquote>\n\n<p>Physical activity level for most people with sedentary lifestyle can be safely assumed to be 1.53 (a gross generalisation). So using 1.53 in the above formula, the caloric requirement comes down to</p>\n\n<blockquote>\n <p><strong>daily requirement in kcal/kg = (24 X 1.53 X wt in kg)</strong></p>\n</blockquote>\n\n<p>So for a 72 kg male, with no other co-morbidities with sedentary lifestyle who looks to maintain wait, the caloric requirement is 2644 kcals per day. If you have an active lifestyle, then replace 1.53 with 1.8 and then the formula becomes </p>\n\n<blockquote>\n <p><strong>daily requirement in kcal/kg = (24 X 1.8 X wt in kg)</strong></p>\n</blockquote>\n\n<p>Since PAL(physical activity level) varies from individual to individual, giving the same formula to everyone is not right. However, these are safe approximations. This page gives a table of approximate PALs. </p>\n\n<p><a href=\"http://www.ivyroses.com/HumanBiology/Nutrition/Physical-Activity-Level.php\" rel=\"nofollow\">http://www.ivyroses.com/HumanBiology/Nutrition/Physical-Activity-Level.php</a></p>\n", "score": 4 } ]
382
CC BY-SA 3.0
What should my daily intake of calories be?
[ "nutrition" ]
<p>How can an adult in robust health find out how many calories his daily intake needs to be?</p> <p>I'm not asking for loss/gain of weight; simply to maintain my weight.</p>
8
https://medicalsciences.stackexchange.com/questions/383/is-it-ok-to-snack-on-salted-nuts-for-a-high-fibre-diet
[ { "answer_id": 386, "body": "<p>Like most foods, salt should be consumed in moderation. Your body needs salt, but a good idea would be to try and cut down salt from some other parts of your diet. For example, get unsalted fries or no ketchup. Check the daily recommended value for an estimate of how much salt you're intaking. Furthermore (thanks to Carey Gregory for pointing this out), drinking water may NOT be the best idea to offset the sodium intake. According to dietitian Monica Reinagel(from LiveStrong link), </p>\n\n<blockquote>\n <p>\"drinking some extra water after a high-sodium meal may help flush\n some of the sodium from your body and may also help get rid of some\n retained water to reduce bloating...</p>\n \n <p>Just drinking more water, however, is <strong><em>not a solution for a long-term\n high-sodium diet</em></strong>, says Reinagel. The increased blood volume that\n results from your body holding onto the excess water is what <strong>raises\n your blood pressure</strong>.</p>\n</blockquote>\n\n<p>So depending on the rest of your diet, you could better judge for yourself whether salted nuts are ok, or maybe unsalted would be better.</p>\n\n<p>If you happen to have a high-sodium diet and don't like the taste of unsalted nuts, it would be a good time to look into alternative sources of fiber.</p>\n\n<p><a href=\"http://www.health.harvard.edu/newsletter_article/salt-and-your-health\" rel=\"nofollow\">http://www.health.harvard.edu/newsletter_article/salt-and-your-health</a></p>\n\n<p><a href=\"https://en.wikipedia.org/wiki/Hygroscopy\" rel=\"nofollow\">https://en.wikipedia.org/wiki/Hygroscopy</a></p>\n\n<p><a href=\"http://jap.physiology.org/content/65/1/332.short\" rel=\"nofollow\">http://jap.physiology.org/content/65/1/332.short</a></p>\n\n<p><a href=\"http://www.livestrong.com/article/529042-does-drinking-water-flush-out-sodium-in-the-body/\" rel=\"nofollow\">http://www.livestrong.com/article/529042-does-drinking-water-flush-out-sodium-in-the-body/</a></p>\n\n<p>Interesting Read if you want to know more about sodium removal from body- </p>\n\n<p><a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2267797/\" rel=\"nofollow\">ncbi.nlm.nih.gov: Sweat rate and sodium loss during work in the heat</a></p>\n", "score": 5 } ]
383
CC BY-SA 3.0
Is it OK to snack on salted nuts for a high-fibre diet?
[ "diet", "fibre" ]
<p>I like to snack on nuts as part of ensuring a high-fibre diet, but I prefer the taste of salted nuts over non-salted. Will eating salted nuts cause me significant dehydration or other health issues? Is it likely to cause me to have too high a daily salt intake? Or is it basically OK?</p>
8
https://medicalsciences.stackexchange.com/questions/408/is-eating-ones-dinner-right-before-going-to-sleep-bad-for-health
[ { "answer_id": 414, "body": "<p>If you eat a lot of food, your stomach will be full. And if you lie down immediately after that, your horizontal posture would put the food (and the acid) in such a way that it puts lot more pressure on the lower esophageal sphincter. If you are a patient of acid reflux disease (or if you have a comparitively weak sphincter and are pre-disposed to develop acid reflux disease), then doing this would greatly increase your chances of developing it. So lifestyle modifications doctors prescribe to patients of acid reflux disease is that:</p>\n\n<ol>\n<li>Eat in small quantities, and in multiple meals</li>\n<li>Give a time gap between dinner and sleep</li>\n<li>Elevate head end of your bed when you go to sleep. </li>\n</ol>\n\n<p>Acid reflux during sleep is notorious because</p>\n\n<ol>\n<li>It damages the mucosa (from below upwards, all of it) making the patient susceptible to Barrett's oesophagus and Oesophageal Ca</li>\n<li>Acid refluxing into the mouth would mean poor oral hygiene, bad breath in the morning, slowly degrading tooth</li>\n<li>Aspiration of acid can damage the larynx and can cause Ca Larynx, and can even cause chemical pneumonitis. </li>\n</ol>\n\n<p>References: </p>\n\n<ol>\n<li><p><a href=\"http://www.webmd.com/heartburn-gerd/guide/what-is-acid-reflux-disease\" rel=\"nofollow\">What Causes Acid Reflux Disease?</a></p></li>\n<li><p><a href=\"http://www.mayoclinic.org/diseases-conditions/gerd/basics/complications/con-20025201\" rel=\"nofollow\">GERD Complications</a></p></li>\n</ol>\n", "score": 7 } ]
408
CC BY-SA 3.0
Is eating one&#39;s dinner right before going to sleep bad for health?
[ "nutrition", "sleep" ]
<p>I often read or hear that eating one's dinner right before going to sleep is bad for health. How true is that?</p>
8
https://medicalsciences.stackexchange.com/questions/417/how-long-is-someone-infectious-after-a-cold
[ { "answer_id": 419, "body": "<p><strong>Tl;dr</strong> - More contagious at the beginning, much less at the end.</p>\n\n<p>The \"common cold\" (or upper respiratory infection) is associated with over 200 different viral types<sup><a href=\"http://en.wikipedia.org/wiki/Common_cold#Virology\">1</a></sup>, and many times more than one virus is present. Because of this, there's probably no <em>completely</em> specific answer to this question, but it can be answered generally.</p>\n\n<p>Rhinovirus-caused colds (which are a large majority of \"common\" colds) are typically contagious at the beginning, and are much less contagious after a few days<sup><a href=\"http://cid.oxfordjournals.org/content/23/6/1287\">2</a></sup>. You are most at risk of transmitting the virus to someone else for the 4-5 days after being <em>exposed</em> yourself<sup><a href=\"http://goaskalice.columbia.edu/when-are-colds-contagious\">3</a></sup> - not necessarily when symptoms appear.</p>\n\n<p>In other words, you can definitely be asymptomatic and still contagious. On the other hand, if you still feel symptoms after a week, the chances are much lower that you're actually still contagious.</p>\n\n<hr>\n\n<p>References:</p>\n\n<p>1: <a href=\"http://en.wikipedia.org/wiki/Common_cold#Virology\">Common Cold: Virology (wikipedia)</a></p>\n\n<p>2: <a href=\"http://cid.oxfordjournals.org/content/23/6/1287\">Incubation Periods of Experimental Rhinovirus Infection and Illness</a></p>\n\n<p>3: <a href=\"http://goaskalice.columbia.edu/when-are-colds-contagious\">When are colds contagious?</a></p>\n", "score": 11 } ]
417
CC BY-SA 3.0
How long is someone infectious after a cold?
[ "common-cold" ]
<p>How long is someone infectious after a cold? </p> <p>I am talking about a common cold, not something extreme.</p>
8
https://medicalsciences.stackexchange.com/questions/454/how-to-know-whether-phrase-a-causes-less-stress-on-my-vocal-cords-than-phrase-b
[ { "answer_id": 600, "body": "<p>You produce sound by flowing air through your <a href=\"http://en.wikipedia.org/wiki/Vocal_folds#Oscillation\" rel=\"nofollow\">vocal folds and making them oscillate</a>. <strong>More</strong> oscillations produce a <em>higher</em> sound frequency, while <strong>less</strong> oscillations produce a <em>lower</em> sound frequency. </p>\n\n<p>You can <strong>also alter the shape</strong> of your <code>folds</code> and <code>mouth</code> to produce different sounds and words. </p>\n\n<p>The above taken into consideration, I'd <strong><em>choose words that cost the least amount of effort</em></strong> to produce. </p>\n\n<p><strong>Frequencies:</strong>\nLow frequencies put less strain (less oscillations) on the folds, however you might need more air flow (lung pressure) to create the volume required for the speech recognition. </p>\n\n<p><strong>Sounds:</strong> As far as the altering of the shape of your mouth and vowels goes, I think eventually a certain type of <em>repetitive strain injury</em> could occur depending on often you use the words.</p>\n\n<p>Also consider this: if your mouth is <strong>closed</strong> at rest, try to pronounce: \"up\". Now try the same starting with your mouth <strong>opened</strong>. In the former case you first need to open your mouth, while in the latter you can start by flowing air. </p>\n\n<p>Look closely at the amount of effort you have to put into producing a certain word. Depending on your 'natural voice' (having a certain frequency), your lung capacity and your resting position you should decide what feels most comfortable.</p>\n\n<p><strong>Regarding \"touch\" and \"click\"</strong> - \nThe <em>'ou'</em> in <code>touch</code> tends to have lower frequencies than the <em>'ick'</em> in <code>click</code>. Also to connect the <em>'c'</em> to the <em>'l'</em> in <code>click</code> you have to move the tip of your tongue to touch right behind your teeth in your upper jaw, whereas this is already the starting position for the <em>'t'</em> in <code>touch</code>.</p>\n", "score": 3 } ]
454
CC BY-SA 3.0
How to know whether phrase A causes less stress on my vocal cords than phrase B?
[ "computers", "voice" ]
<p>Say I have 2 English phrases A and B. How to know whether phrase A causes less stress on my vocal cords than phrase B? A and B are short phrases, ranging from 1 to 4 words. I use them as voice commands in my speech recognition system, which I continuously use throughout the day.</p> <p>E.g. <code>touch</code> vs. <code>click</code>: I have been told that <code>touch</code> put less stress on my vocal cords than <code>click</code>.</p>
8
https://medicalsciences.stackexchange.com/questions/455/topical-nifedipine-cream-and-hypotension
[ { "answer_id": 467, "body": "<p><a href=\"http://www.nlm.nih.gov/medlineplus/druginfo/meds/a684028.html\">Nifedipine</a> is a <a href=\"http://en.wikipedia.org/wiki/Dihydropyridine\">dihydropyridine</a> calcium channel blocker. As you point out, it is used via oral administration for treatment of hypertension. Its effects are mediated primarily by blocking <a href=\"http://en.wikipedia.org/wiki/L-type_calcium_channel\">voltage-dependent calcium channels</a> in the walls of systemic vasculature, causing vasodilation. This has the effect of lowering blood pressure. </p>\n\n<p>Your question, then, rests on whether the nifedipine applied topically to the anus will reach the calcium channels in the vasculature. This is: <strong>is topical nifedipine systemically absorbed to a clinically relevant extent?</strong> </p>\n\n<p>The answer, based on the research I can find, is no. This was explored directly in a study<sup>1</sup>: <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/17163278\">Serum levels and possible haemodynamic effects following anorectal application of an ointment containing nifedipine and lignocaine : a study in healthy volunteers.</a> The authors used 3 g of an ointment containing 0.3% w/w<sup>2</sup> nifedipine, applied twice daily for 7 days. Serum levels of nifedipine were below the below the limits of quantification, consistent with therapeutically negligible concentrations. Mean blood pressure was not changed when compared to baseline.</p>\n\n<hr>\n\n<p><sub>\nNotes\n</sub></p>\n\n<p><sub>\n1. <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/17163278\">Perrotti P1, Grumetto L, Barbato F, Antropoli C. Clin Drug Investig. 2006;26(8):459-67.</a> Note: I was not able to locate a free full text version of this. All of the information reported in my answer is verifiable using the abstract at the link provided. If you would like more information about the specifics of methodology, please fell free to ask in comments or ping me in chat.\n</sub> </p>\n\n<p><sub>\n2. Weight/weight. If the concentration is significantly higher, the answer may be different.\n</sub></p>\n", "score": 7 } ]
455
CC BY-SA 3.0
Topical nifedipine cream and hypotension
[ "medications", "blood-pressure" ]
<p><a href="http://en.wikipedia.org/wiki/Nifedipine">Nifedipine</a> usually is used against high blood pressure. </p> <p>Also nifedipine cream is used for treatment of anal fissures.</p> <p>Can the topical cream applied anally also cause hypotension? </p>
8
https://medicalsciences.stackexchange.com/questions/482/what-is-irons-role-in-oxygenation-in-the-human-body
[ { "answer_id": 485, "body": "<p>This a vast topic, and sorry for the superficial nature of my answer. </p>\n\n<p>Iron is an essential component of <a href=\"http://en.wikipedia.org/wiki/Hemoglobin\">hemoglobin</a>. Hemoglobin is a coloured pigment which binds to oxygen and carries it across the body. It binds to oxygen at a place where there is high oxygen tension (for example, lungs) and release it at a place where there is low oxygen tension (such as the tissues). Iron atoms exist as Fe2+ within the hemoglobin molecules. When oxygen is added to those atoms, they bind to the iron and this prevents the oxygen from leaving it. Oxygen only leaves the iron when it reaches the tissues. So basically you need iron to carry oxygen across the body, because iron (in hemogloobin) is the oxygen carrier.</p>\n\n<p>If a person have a high oxygen requirement at the tissues (such as an athlete), then the body looks to produce more red blood cells (within which the hemoglobin recides) so that it can increase the overall oxygen carrying capacity of the blood. So in order to do that, the body needs needs more iron. So atheletes needs to take more iron because</p>\n\n<ol>\n<li><p>There is a progressively increasing need for more hemoglobin</p></li>\n<li><p>There is a need to maintain the large red blood cell mass that are already existing</p></li>\n</ol>\n\n<p>RBCs die after their life span of 120 days. So there is a constant rate of RBC production and killing of them. And then there is iron loss from body in various forms. The body has a store of iron (in liver). So if there is not enough supply of iron (as in pure vegetarians who does not take proper amount of green leafy vegetables), then the body will start utilising those iron stores. When the stores are over, then the body will start exhibiting symptoms of <a href=\"http://en.wikipedia.org/wiki/Iron_deficiency\">iron deficiency</a>. In order to solve that deficiency, various iron preparations can be prescribed, and Iron tablets are only one of them. </p>\n\n<p>So as I had described, athletes may need a higher iron supply than normal people. In addition to that, there are other people too, who need higher iron input in their diet:</p>\n\n<ol>\n<li><p>Pregnant women (they are prescribed iron and folic acid tablets during gestation)</p></li>\n<li><p>Menstruating women (there is monthly blood loss, and hence iron loss)</p></li>\n<li><p>Growing children (constantly increasing RBC mass, and other growth demands)</p></li>\n<li><p>People with problems in iron absorption</p></li>\n<li><p>People living in the mountains</p></li>\n</ol>\n\n<p>If there is a need to supplement, that can be done using the iron preparations I was talking about. Out of all ingested iron, at most 10-20% is only absorbed. However, the beauty of the human <a href=\"http://en.wikipedia.org/wiki/Human_iron_metabolism\">iron metabolism</a> is that it is strongly regulated. Body will only absorb iron if it is needed. If there is adequate iron in the body already, then the absorption mechanisms are downregulated. However, in overdose, these <a href=\"http://lifeinthefastlane.com/toxicology-conundrum-034/\">mechanisms are deranged</a> and hence there will be over absorption. This occurs more commonly in pediatric age groups who accidentally consumes excess of iron tablets. In those patients the iron gets accumulated in blood (and not in the RBCs are hemoglobin) and harms the cells by various ways. The only way for body to get rid of excess iron is by loss of red blood cells. Hence iron supplementation has to be a carefully monitored procedure. </p>\n\n<p>Hence iron is an absolute necessity in carrying oxygen around in the body. </p>\n", "score": 11 } ]
482
CC BY-SA 3.0
What is iron&#39;s role in oxygenation in the human body?
[ "breathing", "oxygenation", "overdose", "iron-supplements" ]
<p>I hear about runners who need to put more iron in their diet, but then also about toddlers overdosing. I'm wondering what purpose iron serves in carrying oxygen through the body.</p>
8
https://medicalsciences.stackexchange.com/questions/531/effects-of-x-rays-on-the-human-body
[ { "answer_id": 544, "body": "<p>A person should undergo Xrays as often an they are <em>necessary</em>, because the risk-to-benefit ratio is usually very far in favor of the benefit.</p>\n\n<p>As an example of this idea of risk-to-benefit ratio, lets take getting into a car.</p>\n\n<p>There is <strong>always</strong> a risk to getting into a car. After all, they move quickly, slide on slippery roads, and hurl towards (and potentially <em>at</em>) each other at a frightening rate of speed. You probably know someone who died in a car accident. Yet, probably without giving it a single thought - except when you're buckling your seat belt - you get into a car several times per day/week. Because the benefit (distance transportation, convenience) is higher than the risk of injury in a motor vehicle accident (this example is actually flawed, but we'll ignore that for the moment.)</p>\n\n<p>Similarly, there is <strong>always</strong> a risk to getting an xray, but sometimes you just have to get them. The risk is low compared to the benefit. You wouldn't want anyone putting you in a cast without knowing what kind of bone fracture you had, because some kinds need to be casted differently, some need to be casted longer, some need operative repair, and some only need a splint. The benefit outweighs the risk.</p>\n\n<p>There is no completely safe lower limit of radiation. Radiation (especially in fetuses and children) increases the likelihood of cancer. Our information comes mostly from atomic bomb survivors, people exposed at Chernobyl (nuclear reactor accidents), people treated with high doses of radiation for cancer and other conditions, and people exposed to high levels of background radiation, e.g. uranium miners.</p>\n\n<p>Radiation doses are measured in <a href=\"http://www.epa.gov/radiation/understand/perspective.html\" rel=\"nofollow\">millisieverts</a> (mSv). For comparison's sake, you should know that, depending on where you live, </p>\n\n<ul>\n<li>natural background radiation exposure accounts for an average of <strong>3.1 mSv/yr</strong></li>\n<li>A seven hour airplane trip exposes you to <strong>0.02 mSv</strong> of radiation per trip</li>\n<li>Backscatter Wave Scanners in airports exposure is just less than 0.0001 mSv per scan (so one average year exposes you to 31,000 times as much radiation as an airport scanner.)</li>\n<li>a four bite-wing dental series is about 0.005 mSv</li>\n<li>a two view Chest X Ray doses you 0.1 mSv</li>\n<li>your average CT scan is going to give you 7 mSv of exposure </li>\n</ul>\n\n<p>Is that safe? What is your chance of getting a lethal cancer from that? The answer is: no one knows. It depends on a lot of unmeasurable things: genetics, your age, your ability to repair the damage, which area of the body is being dosed, whether there are other carcinogens at work (e.g. viruses or co-carcinogens), etc.</p>\n\n<p>The following all give you a (estimated) <em>1 in a million</em> chance of dying from that event:</p>\n\n<blockquote>\n <ul>\n <li>Smoking 1.4 cigarettes (lung cancer)</li>\n <li>Eating 40 tablespoons of peanut butter</li>\n <li>Spending 2 days in New York City (air pollution)</li>\n <li>Driving 40 miles in a car (accident)</li>\n <li>Flying 2500 miles in a jet (accident)</li>\n <li>Canoeing for 6 minutes</li>\n <li>Receiving 10 mrem (.1 mSv) of radiation (cancer)</li>\n </ul>\n</blockquote>\n\n<p>So, you can estimate that (maybe) the risk of dying from a 7 mSv CT scan is about equivalent to driving 2800 miles.</p>\n\n<p>Taken individually: </p>\n\n<blockquote>\n <p>What is the maximum number of times a person can undergo x-ray scanning? </p>\n</blockquote>\n\n<p>As often as necessary. As long as the benefit outweighs the risk.</p>\n\n<blockquote>\n <p>Is their a maximum limit? If so, what are the side effects that the person will be subjected to if he undergoes x-ray scanning more number of times?</p>\n</blockquote>\n\n<p>No, there's no maximum limit. The risk is cancer. The risk is low, but not negligible. It doesn't go up linearly with every Xray study you have.</p>\n\n<blockquote>\n <p>Are they life threatening and do they have long term effects on the body of the person?</p>\n</blockquote>\n\n<p>Yes; cancers are often life threatening.</p>\n\n<p>What can you do about it?</p>\n\n<ul>\n<li>Don't ask your doctor for an unnecessary Xray.</li>\n<li>Ask your doctor if an Xray they ordered is necessary (sometimes they are ordered to reassure the patient - or their parents, in the case of head injury - that nothing is wrong.) A doctor worth their salt will respect you for asking. Sometimes it's ok to take a \"wait-and-see\" approach. Sprained ankles meeting certain criteria never need an Xray. It's ok to ask.\n_ If your doctor orders a CT scan of something, ask if an MRI would be better. (They cost more, and are sometimes as good or better than a CT scan.)</li>\n<li>wear a shield when offered (will shield the parts of your body they don't need to see.</li>\n<li>ask about the age of the machine (newer machines often use lower dosages than older ones (post 2005 is better).</li>\n</ul>\n\n<p><sub><a href=\"http://www.xrayrisk.com/faq.php#q20\" rel=\"nofollow\">X Ray Risk.com</a></sub><br>\n<sub><a href=\"https://radiology.ucsf.edu/patient-care/patient-safety/radiation-safety/risks-of-radiation\" rel=\"nofollow\">Risks of Radiation</a></sub><br>\n<sub><a href=\"http://www.physics.isu.edu/radinf/risk.htm\" rel=\"nofollow\">Radiation and Risk</a></sub><br>\n<sub><a href=\"http://www.epa.gov/radiation/understand/health_effects.html#est_health_effects\" rel=\"nofollow\">Radiation Protection</a></sub><br>\n<sub></sub><br>\n<sub></sub><br>\n<sub></sub></p>\n", "score": 6 } ]
531
CC BY-SA 3.0
Effects of X-rays on the human body
[ "side-effects", "radiology" ]
<p>What is the maximum number of times a person can safely undergo x-ray scanning? If this limit is exceeded, are there serious and/or life threatening side effects that the person may experience?</p>
8
https://medicalsciences.stackexchange.com/questions/590/rationales-behind-the-order-of-applying-the-torso-straps-of-a-kendrick-extricati
[ { "answer_id": 596, "body": "<p>Kendrick Extrication Devices (KED) are used during extrications (Such as in automobiles) where space is limited, and a backboard can't be used safely.</p>\n\n<p>Generally the mnemonic for securing the straps is My Baby Looks Hot Tonight.</p>\n\n<ul>\n<li>Middle</li>\n<li>Body (Torso)</li>\n<li>Legs</li>\n<li>Head</li>\n<li>Top</li>\n</ul>\n\n<p>It is to be noted, that recently in the US, the recommended order is My Baby Looks Totally Hot, recommending securing the Top before the Head.</p>\n\n<p>Some of the reasons behind the order are that if the top is secured first, it creates uneven pressures (Think of a teeter totter, securing one end pushes the other away), and that securing one end does not prevent the other from sliding around. This is why torso and body are secured first.</p>\n\n<p>According to the <a href=\"http://en.wikipedia.org/wiki/Kendrick_Extrication_Device\" rel=\"nofollow\">wiki entry</a>, there is no peer reviewed support for preferred strap order:</p>\n\n<blockquote>\n <p>An exhaustive search of the literature for peer reviewed scientific data regarding the positive or negative effects of application of the K.E.D. straps in any specific order found no results. It is likely such data does not exist, and that there are valid arguments on both sides of the issue. However, best practices indicate that the manufacturer's directions should be followed whenever using any piece of medical equipment. That being said, whenever the EMS professional is in doubt about a medical procedure it is advisable to contact your local medical director.</p>\n</blockquote>\n\n<p>The most recent user manual that I could find is dated 2001, and it recommends the MBLHT order of strap securing. I did find a <a href=\"http://www.ct.gov/dph/lib/dph/ems/pdf/communication_statements/2009_01_Updated_KED_Clarification_Memo.pdf\" rel=\"nofollow\">clarification memo from the State of Connecticut</a> dated 2009, which states that they will be following the manufacturers recommendation:</p>\n\n<blockquote>\n <p>Teaching and testing standards for long backboard and short spine board fixation sequences have always been clear. Criteria identified by the National Registry and observed by OEMS for several years have identified that the sequence for both long and short spinal immobilization\n devices should be in the following order:</p>\n</blockquote>\n\n<pre><code> 1. Torso fixation\n 2. Leg fixation\n 3. Head fixation\n</code></pre>\n\n<blockquote>\n <p>Many of the commonly used EMT-Basic and Paramedic texts have also identified this sequence as the standard. However, the Kendrick Extrication\n Device (KED) product manual suggests that the top torso strap be secured last, and after the head is secured. This apparent “exception to the\n rule” may have contributed to student, instructor and examiner confusion. </p>\n \n <p>The Office contacted the Ferno –Washington, Inc., the manufacturers of the KED for clarification. Based on responses from Ferno spokespeople and effective immediately, the expected sequence of strap application in the Spinal Immobilization - Seated (if the KED is used) will be: Middle Strap, Lower Strap, Leg Straps, Head Immobilization and lastly the Top Strap,\n as described in the Ferno KED user manual.</p>\n</blockquote>\n\n<p>However, these are all dating from up to 2009, and several forum postings from 2011 and later suggest that the order changed, and this is supported by the <a href=\"https://www.nremt.org/nremt/downloads/E211%20Spinal%20Immobilization%20Seated.pdf\" rel=\"nofollow\">testing sheet currently in use</a> by the National Registry for EMT's (NREMT) in the United States. </p>\n\n<pre><code>Secures the device to the patient’s torso\nEvaluates torso fixation and adjusts as necessary\nEvaluates and pads behind the patient’s head as necessary\nSecures the patient’s head to the device\n</code></pre>\n\n<p>Further supporting this is <a href=\"https://books.google.com/books?id=PJyhIH8N8qgC&amp;pg=PA1193&amp;lpg=PA1193&amp;dq=Kendrick%20extrication%20user%20manual&amp;source=bl&amp;ots=aPWUrVa-AN&amp;sig=CrbbQGCXTAIuTxmLn_IIzhCigsI&amp;hl=en&amp;sa=X&amp;ei=I181VeikAYX7oQT_z4GoBA&amp;ved=0CCgQ6AEwAjgU#v=onepage&amp;q=Kendrick%20extrication%20user%20manual&amp;f=false\" rel=\"nofollow\">Mosby's Paramedic Manual</a> which also specifies the head being last (Step 4).</p>\n\n<p>In the absence of evidence to the contrary (Such as a current user manual), I would state that the current recommendation in the United States is the MBLTH order, with the head being last. (It is to note that this is different than when I was certified EMS, in that the Top was the last strap, not the Head).</p>\n\n<p>As far as the differences between different countries/districts, I would posit that they are following whatever protocol exists, and it either was not updated, or there was a feeling that no update needed to be made in this case. Hardly definitive, but this is the most that I could find that is in any way current enough to be relative.</p>\n", "score": 3 } ]
590
CC BY-SA 3.0
Rationales behind the order of applying the torso straps of a Kendrick Extrication Device
[ "first-aid", "procedural-expectations", "emt", "torso" ]
<p>The <a href="http://www.interieur.gouv.fr/content/download/36656/277162/file/PSE2.pdf">French team first-aid guidelines</a> define that the torso straps of a <a href="http://en.wikipedia.org/wiki/Kendrick_Extrication_Device">KED</a> should be fastened and secured in the following order: middle, low, top. </p> <p>(This order seems to be the same in other countries, like <a href="http://www.mums.ac.ir/shares/darman/emergency/ked0102_000.pdf">Ireland</a>, where the straps are placed in a slightly different order but secured in exact same order.)</p> <p>Is this a result driven difference, or is there another rationale?</p>
8
https://medicalsciences.stackexchange.com/questions/656/long-term-effects-of-lens-removal-as-the-vitreous-ages
[ { "answer_id": 659, "body": "<blockquote>\n <p>...it seems possible that with aging, as the vitreous becomes less distinct from the aqueous, some of the vitreous might end up draining through the same duct that the aqueous drains through, in an eye with no lens to serve as a barrier. Is that the case?</p>\n</blockquote>\n\n<p>In a normal (i.e. lens intact) eye, that would, I think, be a problem.</p>\n\n<p>The aqueous humor is a self-replenishing system, whereas the vitreous humor is made and completed before birth. There is no replenishment of it, although, because it is near a capillaries bed, there is diffusion of small molecules like glucose back and forth that takes place between the blood and the vitreous humor.</p>\n\n<p>You're correct that the vitreous humor (initially a very well organized gel-like substance) liquifies as aging occurs, but the predominant effect of this is floaters (vitreous detachments*), retinal pulls, tears, hemorrhages and detachments.</p>\n\n<p><img src=\"https://i.stack.imgur.com/GcKKZ.gif\" alt=\"enter image description here\"></p>\n\n<p>Fluid (aqueous humor) is produced by cells in the ciliary body (which is part of the ciliary muscle, with ligamentous connections to the edge of the lens) behind the iris. This fluid-filled space is called the posterior chamber. The fluid then passes from behind the iris into the anterior chamber, between the iris and the cornea, and finally drains through a permeable network (the trabecular meshwork) near the base of your the anterior part of the iris. So, there is constant production and drainage of aqueous humor, keeping the fluid level balanced.</p>\n\n<p>When too much fluid is made, or not reabsorbed, the anterior chamber bulges, deforming the shape of the vitreous humor and placing pressure on the optic nerve. There is no fluid exchange between the two unless there is disease of the posterior chamber.</p>\n\n<p>When the vitreous humor liquifies, the volume stays the same. If it could drain out of the trabecular meshwork, I would imagine there would be a much greater risk of more serious vitreous detachments and subsequent retinal detachments.</p>\n\n<p>In the case of a lens removed in childhood, the vitreous humor, being a highly organized gel, is probably little affected by lens removal. With age, because liquifaction happens from the middle of the vitreous; the effect of loss of the lens is still probably small, but I imagine - I'm not an opthalmologist - it might be different for someone who has had a lifetime to accommodate. </p>\n\n<p>(I might have to read and edit this answer again.)</p>\n\n<p>*<sub>Not the sole cause of floaters</sub><br>\n<sub>cross-section image from <a href=\"http://www.patient.co.uk/health/acute-angle-closure-glaucoma\" rel=\"nofollow noreferrer\">Patient.co.uk: Acute Angle-closure Glaucoma</a></sub><br>\n<sub><a href=\"https://www.dartmouth.edu/~humananatomy/part_8/chapter_46.html\" rel=\"nofollow noreferrer\">https://www.dartmouth.edu/~humananatomy/part_8/chapter_46.html</a></sub><br>\n<sub><a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1770054/\" rel=\"nofollow noreferrer\">J Clin Pathol. 2003 Sep; 56(9): 720: Concurrent vitreous disease may produce abnormal vitreous humour biochemistry and toxicology</a></sub></p>\n", "score": 6 } ]
656
CC BY-SA 3.0
Long-term effects of lens removal as the vitreous ages?
[ "ophthalmology", "aging" ]
<p>In a case of pediatric cataract surgery where the lens was not replaced, there is no lens to serve as a barrier between the aqueous and the vitreous. I once asked an ophthalmologist what keeps them from mixing together in that case -- are they of different viscosities, like oil and water, for instance? She said it's something like that, but that with aging the vitreous gradually thins (causing floaters, among things) and they end up blending together. She said this isn't really a problem in practice, as each humour's main function is to deliver nutrients to the right parts of the eye and they can still do that.</p> <p>I understand that the aqueous drains through a duct, so that part isn't a closed system. But the vitreous usually is a closed system, as I understand it, which is why floaters don't go away. A remedy for floaters that is sometimes brought up is <a href="http://en.wikipedia.org/wiki/Vitrectomy" rel="nofollow">vitrectomy</a>, but that carries risk of retinal detachment (according to Wikipedia, and I think I remember hearing that from an ophthalmologist too).</p> <p>Putting all of these together, it seems possible that with aging, as the vitreous becomes less distinct from the aqueous, some of the vitreous might end up draining through the same duct that the aqueous drains through, in an eye with no lens to serve as a barrier. Is that the case? And if it is, does it carry with it a higher risk of the things that can go wrong with vitrectomy (especially retinal detachment)? Or does the risk that comes with that procedure not arise with a slow, gradual aging process?</p> <p>Update: I've seen a reference to the <a href="http://en.wikipedia.org/wiki/Vitreous_membrane" rel="nofollow">hyaloid membrane</a>, which, in addition to the lens, sits between the vitreous and aqueous. I don't know if this membrane is also removed when a lens is removed or if it remains.</p>
8
https://medicalsciences.stackexchange.com/questions/663/when-someone-with-glaucoma-sees-rainbows-around-lights-what-exactly-is-happenin
[ { "answer_id": 986, "body": "<p>The so-called halos are typical for spikes of intraocular pressure rise in high-tension glaucoma (or ocular hypertension) forms, most often in <a href=\"http://onlinelibrary.wiley.com/doi/10.1111/j.1442-9071.2009.01920.x/full\" rel=\"nofollow\">melanin-dispersion syndrome (MDS, or pigment-dispersion syndrome)</a> which is a trigger for glaucoma in myopes and often begins in early adulthood. </p>\n\n<p>The halos appear when a spike in intraocular pressure leads to <a href=\"http://www.eyecalcs.com/DWAN/pages/v4/v4c016a.html\" rel=\"nofollow\">intracorneal edema</a>, as the corneal endothelial cells which permanently pump the nutritious water out of the cornea cannot compete with the high pressure pushing the fluid into the cornea anymore. Thus, the cornea fills with water, leading to temporary loss of visual acuity and, as an early symptom, to halos and rainbows around sources of light due to increased dispersion of light. The regularity of the extracellular matrix, which is crucial for corneal transparency, is disturbed by the intrusion of water leading to cell displacement.</p>\n\n<p>Basically, this can happen in other forms of high-tension glaucoma or ocular hypertension with momentarily raised intraocular pressure (IOP), too. Note that it only does in forms where the IOP rises quickly, whereas in a slow and constant rise (as it happens in many forms of chronic glaucoma) the endothelial cells can adapt and still drain the cornea from the excess water. So basically, the same happens in an attack of angle-closure glaucoma, just with the difference being that angle-closure glaucomas often don't go away without medical treatment, whereas in early adulthood IOP spikes due to MDS the halos often are the only symptom which is often triggered by exercise or in dim ambience light situations. This is due to the fact that when the iris moves (as in widened pupils due to adrenaline reactions when performing sports or whe the lights are dim) in a patient with MDS, it rubs against the lens, loses pigment by erosion and this then <a href=\"http://www.researchgate.net/publication/8527032_Intraocular_pressure_spike_after_YAG_iridotomy_in_patients_with_pigment_dispersion\" rel=\"nofollow\">clogs the eye's drain</a> (in the anterior chamber angle).</p>\n\n<p>This can be seen as basic knowledge in ophthalmology. A first report on the mechanism leading to IOP rise dates <a href=\"http://www.sciencedirect.com/science/article/pii/0002939453907995\" rel=\"nofollow\">back to 1953</a>. The induction of IOP spikes by exercise has also <a href=\"http://www.sciencedirect.com/science/article/pii/0002939480900732\" rel=\"nofollow\">been known for a longer period of time</a>.</p>\n\n<p>EDIT: As your question explicitly relates to open-angle glaucoma, I'd like to add that there are different types of open-angle glaucoma, and only some of them are known for IOP spikes that could lead to said halos and rainbows. Primary open-angle glaucoma usually doesn't, but other than the mentioned pigmentaray dispension syndrome, <a href=\"https://books.google.de/books?id=JZ9Gs3fLqrcC&amp;pg=PA129&amp;lpg=PA129&amp;dq=pex+glaucoma+spikes&amp;source=bl&amp;ots=xeLL-Xtl0G&amp;sig=4bl_Gz93-chlsUZcwbQwbhoPFT0&amp;hl=de&amp;sa=X&amp;ei=cfBZVfPHH8GNsgGkl4CACQ&amp;ved=0CCIQ6AEwAGoVChMIs8SA6bnLxQIVwYYsCh2kCwCQ#v=onepage&amp;q=pex%20glaucoma%20spikes&amp;f=false\" rel=\"nofollow\">PEX glaucoma</a> could, and <a href=\"http://www.oic.it/~egsmadrid2010/pdf/ps3b/P3.148.pdf\" rel=\"nofollow\">herpes simplex trabeculitis</a> is also not uncommon.</p>\n\n<p>The American Academy of Ophthalmology has a <a href=\"http://eyewiki.aao.org/Pigmentary_glaucoma_and_Pigment_Dispersion_Syndrome\" rel=\"nofollow\">good description on pigmentary glaucoma</a> in their EyeWiki.</p>\n\n<p>It can be also found in <em>Clinical Ophthalmology: A Systematic Approach, 7th Edition. Jack J. Kanski, B, Bowling. 2011, Saunders, ISBN 978-0-7020-4093-1, p:365ff.</em>, and extensively in <em>Basic and Clinical Science Course 2007-2008 Section 10: Glaucoma. American Academy of Ophthalmology, 2007, San Francisco, ISBN 978-0-7020-4093-1, p.101-103.</em></p>\n", "score": 9 } ]
663
CC BY-SA 3.0
When someone with glaucoma sees rainbows around lights, what exactly is happening physically?
[ "ophthalmology", "glaucoma", "intraocular-pressure-iop" ]
<p>People with open-angle glaucoma sometimes see halos or rainbows around bright lights (e.g. headlights at night), but not always. Glaucoma results in elevated intraocular pressure and thence pressure on the optic nerve, so it doesn't surprise me that there'd be visual effects -- but why <em>halos</em> and <em>rainbows</em> specifically and not, say, blurry vision or flashes of light or some other deviation from normal vision? And what factors govern when it happens, since it's not a constant state? Is that just caused by minor fluctuations in the pressure level, which I understand varies through the course of the day, or is there some other factor?</p>
8
https://medicalsciences.stackexchange.com/questions/721/what-are-the-possible-health-consequences-of-using-whitening-strips
[ { "answer_id": 1008, "body": "<p>I found a study which show that teeth whitening using Hydrogen Peroxide can cause oral mucosa irritation, burns or sensitive teeth. However, these were found to be mild in nature and resolved spontaneously without any intervention. Since teeth whitening strips are hydrogen peroxide based, I think the results can be safely extrapolated.</p>\n\n<p>References:</p>\n\n<ol>\n<li><a href=\"http://www.ncbi.nlm.nih.gov/pubmed/25799793\" rel=\"noreferrer\">Teeth whitening with 6% hydrogen peroxide vs. 35% hydrogen peroxide, a comparative controlled study</a></li>\n</ol>\n", "score": 7 } ]
721
CC BY-SA 4.0
What are the possible health consequences of using whitening strips?
[ "dentistry", "gums", "white-strips-teeth" ]
<blockquote> <p>Whitening strips are very thin, virtually invisible strips that are coated with a peroxide-based whitening gel. The strips are applied twice daily for 30 minutes for 14 days. Initial results are seen in a few days and final results are sustained for about four months. <a href="http://www.webmd.com/oral-health/teeth-whitening">{1}</a></p> </blockquote> <p>However, I heard from someone that whitening strips can cause gum deterioration.</p> <p>Are there studies that indicate teeth-whitening strips have negative consequences on teeth or general health?</p>
8
https://medicalsciences.stackexchange.com/questions/892/how-much-alcohol-intake-is-required-to-trigger-withdrawal
[ { "answer_id": 905, "body": "<p>I don't think that you will find a definitive answer on this, unfortunately. There are too many factors on an individual basis to make it a blanket kind of projection. The closest that I found for any kind of writeup that addresses it is <a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1540391/\" rel=\"noreferrer\">this published article</a>.</p>\n<p>The pertinent part of that is this section here:</p>\n<blockquote>\n<p><strong>How Much Alcohol Must Be Ingested (and over what period) for a Person to Develop Alcohol Dependence and to Be at Risk for Alcohol Withdrawal?</strong></p>\n<p>There is no absolute relationship between pattern of alcohol use and the risks of physiologic dependence and withdrawal, which most likely reflects the significant number of variables, in addition to duration and quantity of alcohol use, that can contribute to dependence and withdrawal risk for a given individual. Some of these additional variables include age, medical comorbidities (such as hepatic dysfunction), concomitant medication use, and seizure threshold.</p>\n<p>It has been easier to quantify the risk of benzodiazepine withdrawal, based on degree of benzodiazepine use (even though benzodiazepines act at the same receptor as does alcohol and are cross-reactive with it). For example, daily use of 20 mg of diazepam for 3 weeks or longer is believed to be sufficient to induce physiologic dependence.<a href=\"http://Gonzales%20JJ,%20Stern%20TA,%20and%20Emmerich%20AD.%20et%20al.%20Recognition%20and%20management%20of%20benzodiazepine%20dependence.%20Am%20Fam%20Phys.%201992%2045:2269%E2%80%932276\" rel=\"noreferrer\">3</a> However, the shorter half-life of alcohol (1–2 hours) has made similar predictions elusive in the case of alcohol abuse. In general, any suspicion of daily alcohol use over several weeks or more, regardless of quantity, should raise concern over possible alcohol withdrawal.</p>\n</blockquote>\n<p>So, while you can make some possible predictions, you may just have to look at the drinking history pattern and project from that, and make preparations for withdrawal symptoms to occur in cases of extended consumption, even if it the first time the patient has consumed in that manner.</p>\n<p>As far as the preparations, there is <a href=\"http://pubs.niaaa.nih.gov/publications/arh22-1/05-12.pdf\" rel=\"noreferrer\">this article</a> which addresses the clinical features, assessment and management of AWS (Alcohol Withdrawal Syndrome).</p>\n", "score": 6 } ]
892
CC BY-SA 3.0
How much alcohol intake is required to trigger withdrawal?
[ "alcohol", "recreational-drugs" ]
<p>Daily heavy alcohol users frequently experience a <a href="http://www.aafp.org/afp/2004/0315/p1443.html">withdrawal syndrome</a> if they suddenly stop drinking. I’m pretty confident that 2 standard drinks per day is rarely enough to trigger withdrawal, and those who drink 8-10/day almost always experience some withdrawal, but I’m not clear on where the line is. I realize there is a lot of inter-individual variability in this, but I’m wondering if it has been investigated systematically. The duration of use clearly also affect this.* </p> <p>Ideally, I would like to see a 3D graph showing the likelihood of withdrawal (at some threshold level of severity) according to daily dosage and length of exposure. Not being confident that this exists, any studies looking into the threshold daily intake required to trigger withdrawal would be welcome.</p> <hr> <p><sub> *There’s also a (somewhat controversial) concept known as <a href="http://pubs.niaaa.nih.gov/publications/arh22-1/25-34.pdf">‘kindling’</a> whereby repeated detox attempts may cause worsening of withdrawal, but for the purpose of this question I’m assuming a first detox attempt. </sub></p>
8
https://medicalsciences.stackexchange.com/questions/901/what-does-prognostic-significance-mean-exactly
[ { "answer_id": 904, "body": "<p>Although it would be helpful if we knew what sort of pathology report this was, I surmise that it is likely describing analysis of a biopsy or surgically removed tissue specimen from a breast cancer.</p>\n\n<p>In breast cancer, <a href=\"http://breast-cancer-research.com/content/16/6/494\">it has long been known</a> that some but not all tumors express hormone receptors, particularly estrogen and progesterone. Although the mechanism is complicated, the basic idea is that estrogen can bind to the cells in the tumor and make it grow faster. For this reason, people with tumors expressing the estrogen receptor are often treated with <a href=\"http://www.cancer.org/cancer/breastcancer/detailedguide/breast-cancer-treating-hormone-therapy\">hormonal therapy</a> that blocks that hormonal stimulation. In pre-menopausal women, this is usually <a href=\"http://www.nlm.nih.gov/medlineplus/druginfo/meds/a682414.html\">tamoxifen</a> or a related drug, which blocks the receptors directly. In post-menopausal women, a class of drugs called aromatase inhibitors (<a href=\"http://www.nlm.nih.gov/medlineplus/druginfo/meds/a696018.html\">anastrozole</a>, letrozole, etc.) that block estrogen production are used. The important piece to note is that only tumors that express estrogen receptors respond to this type of hormonal treatment.</p>\n\n<p>Partly because of the availability of these hormonal treatments, and perhaps partly due to the biology of the tumors themselves, breast cancer that expresses estrogen receptors <a href=\"http://www.cihrt.nl.ca/exhibits/June%2023%20O%20Malley%20Exhibits/P-1720_Article%20entitled%20regarding%20Adjuvant%20Endocrine%20Therapy%20in%20Breast%20Cancer.PDF\">tends to have a better <em>prognosis</em> than estrogen-receptor negative breast cancer.</a> <em>Prognosis</em> can refer to a variety of outcomes; in cancer studies it’s usually either survival or cancer-free survival. Patients with estrogen-receptor positive breast cancer <strong>tend to fare better</strong> than those with estrogen-receptor negative tumors. Another way of stating that is: <strong>the presence of the estrogen-receptor has a <em>favorable prognostic significance.</em></strong></p>\n\n<p>The pathology report (if I’ve got the context correct!) is saying that most (80%) of the cells in the specimen expressed the estrogen receptor. It then comments that this is known to be a favorable finding.</p>\n", "score": 8 } ]
901
What does &quot;prognostic significance&quot; mean exactly?
[ "cancer", "terminology" ]
<p>I am trying to more fully understand a pathologist report and do not know what "Prognostic Significance" means.</p> <p>Example...</p> <pre><code>Estrogen Receptor Result: 80% positive Prognostic Significance: Favorable Reference Range: &gt; 1% </code></pre>
8
https://medicalsciences.stackexchange.com/questions/924/how-to-stop-or-even-reverse-cavities
[ { "answer_id": 943, "body": "<p>I can speak from personal experience, and from experience working as a physical chemist peripherally associated with a group researching dental care.</p>\n\n<p>My personal experience is that I have a few lesions that my various dentists over the last couple of decades have decided not to fill because they are not serious and not getting any worse. So a dentist will not necessarily reach for their drill at every opportunity.</p>\n\n<p>My research experience is that at least <em>in vitro</em> enamel can remineralise, but you are talking about incremental improvements and nothing approaching total repair of a cavity. Any major cavity will not repair itself.</p>\n\n<p>It is impossible for you to assess the damage to your teeth because you have neither the skills nor the equipment required. Your dentist has both, and you should respect their judgement. Your dentist should probably not have been impatient with your questions, but bear in mind that by questioning him you are implying he does not know what he is talking about and even the most saintly of dentists will get fed up with this eventually.</p>\n", "score": 7 }, { "answer_id": 16574, "body": "<p>There are really two different questions posed here:</p>\n\n<blockquote>\n <ol>\n <li>How to stop or even reverse cavities?</li>\n </ol>\n</blockquote>\n\n<p>This is currently only partially possible in the sense of slowing down the further spread and development of caries.<br>\nEliminate acids and sugars from your diet, that includes starches and other cariogenic carbohydrates. Practice impeccable oral hygiene with lots of fluoride toothpaste, interdental cleanig with mouth washes, tooth picks and floss. Drink lots of green tea and milk. All of this – and more, if believe what's floating around the net popularly and mostly falsely – has very limited effects and cannot fully replace a visit to the dentist under any normal circumstances. </p>\n\n<p>Cavities cannot be \"reversed\", that is rebuilt and filled up to a fully working intact tooth. Not with miracle supplements, exotic foods and not even by a dentist, except that a dentist might have suitable substances to fill the cavity.</p>\n\n<p>That answers hypothetically a question with unrealistic goals. </p>\n\n<p>And the real question:</p>\n\n<blockquote>\n <ol start=\"2\">\n <li>What do you in case of a cavity and don't want to go dentist because you fear the side effects of drilling?</li>\n </ol>\n</blockquote>\n\n<p><sub>First thing is of course something of the past in this case: try to prevent the cavity from forming in the first place. this is called prophylaxis and includes the usual: limit carbohydrate contact with teeth, practice oral hygiene and visit a dentist, not to let her drill anything, but to remove calculus and get protective lacquer layers. But as this is apparently too late in a case with developed cavities:</sub></p>\n\n<p>Someone with a cavity who does not want to go to a dentist because of the fear of drilling <em>has</em> to go to the dentist and let her drill and fill. The biggest problem in the scenario presented is <em>not</em> the procedure itself but the anxious anticipation that prevents a necessary and very, very probably best option.</p>\n\n<p>The secret of success is mentioning the anxiety involved and then requesting at least one of the following or even two drugs at once. Most of the time the request will be preempted by an offer:</p>\n\n<ol>\n<li>a large dose of local anaesthetic – for example <a href=\"https://en.wikipedia.org/wiki/Lidocaine\" rel=\"nofollow noreferrer\">Lidocaine</a> – that will prevent any pain from being registered in the brain</li>\n<li>an adequate dose of a one-time anxiety reliever or even a sedative that will make your brain not only dull to the pain but utterly uninterested in the effects for a while that is long enough until the procedure is over</li>\n</ol>\n\n<blockquote>\n <p>Dentists can also prescribe medications such as antibiotics, sedatives, and any other drugs used in patient management.<br>\n <sub><a href=\"https://en.wikipedia.org/wiki/Dentistry#Dental_treatment\" rel=\"nofollow noreferrer\">Wikipedia: Dentistry#Dental treatment</a></sub></p>\n</blockquote>\n\n<p><a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5005095/\" rel=\"nofollow noreferrer\">Current methods of sedation in dental patients - a systematic review of the literature</a> Med Oral Patol Oral Cir Bucal. 2016 Sep; 21(5): e579–e586.\nPublished online 2016 Jul 31. doi:10.4317/medoral.20981</p>\n\n<p>WebMD: <a href=\"https://www.webmd.com/oral-health/sedation-dentistry-can-you-really-relax-in-the-dentists-chair#1\" rel=\"nofollow noreferrer\">Sedation Dentistry: Can You Really Relax in the Dentist's Chair?</a><br>\n<a href=\"https://www.mouthhealthy.org/en/az-topics/a/anesthesia-and-sedation\" rel=\"nofollow noreferrer\">MouthHealthy, ADA, Anesthesia and Sedation</a><br>\n<a href=\"http://www.ada.org/~/media/ADA/Education%20and%20Careers/Files/anesthesia_use_guidelines.pdf\" rel=\"nofollow noreferrer\">ADA Guidelines for the Use of Sedation and General Anesthesia by Dentists 2016</a><br>\n<a href=\"http://www.sedationdentistry4u.com/\" rel=\"nofollow noreferrer\">SedationDentstry4U</a><br>\nInform yourself before requesting any of that and do not fixate on a specific combination, but discuss this with your dentist. </p>\n", "score": 3 }, { "answer_id": 17053, "body": "<p>As I understand it, the current consensus among dentists and scientists is that cavities which have reached the dentin layer are too big to heal using any existing technology, but that carious legions (areas of the tooth that have begun to erode through demineralization) can be remineralized with a lot of methods. Your own saliva contains calcium which regularly remineralizes teeth when conditions are right (mostly that pH is high enough). Almost all toothpastes help remineralize by containing some combination of calcium, phosphorous and/or fluoride.</p>\n\n<p>As has been mentioned by other responses, there is some promising research on repairing teeth with substances like AD drug tidesglusib. None of these treatments, to my knowledge, are ready for non-experimental use. </p>\n\n<p>The reason this problem is so tough is that tooth enamel is not a living structure like much of your bone is. It does not contain any living cells. The pulp in your teeth is alive, and can manufacture a small amount of protective dentin (the intermediate layer) to repair damage from the inside, but hasn't been shown to repair the enamel. Once bacteria have reached the dentin by wearing a cavity all the way through your enamel, there is no easy way to kill that bacteria so it is assumed that it will continue to thrive in the cavity until it reaches the pulp and ultimately destroys the tooth. Fillings are created by removing all the weakened and infected enamel and replacing it with an artificial material to protect the rest of the tooth.</p>\n\n<p>Wikipedia provides references for most of this: <a href=\"https://en.wikipedia.org/wiki/Tooth_decay\" rel=\"nofollow noreferrer\">https://en.wikipedia.org/wiki/Tooth_decay</a></p>\n\n<p>And here is the information about tidesglusib, which is expected to begin human trials in 2019:\n<a href=\"https://epatientfinder.com/human-trials-regrowing-teeth-expected-start-2019/\" rel=\"nofollow noreferrer\">https://epatientfinder.com/human-trials-regrowing-teeth-expected-start-2019/</a></p>\n\n<p>In answer to your second question, the best thing to do to start out is to get a dental x-ray. This will show you how deep the cavity has penetrated and you may well be able to stop its progress by stepping up your dental care and nutrition, making a filling unnecessary. </p>\n", "score": 2 }, { "answer_id": 17067, "body": "<p>There were two questions here, but I'm only going to respond to the one in the headline \"How to stop or even reverse cavities?\" with one possibly helpful ingredient of the puzzle.</p>\n\n<p>Besides the regular brushing advice that dentists have been giving for decades, a more recent discovery is the benefits of <a href=\"https://en.wikipedia.org/wiki/Xylitol\" rel=\"nofollow noreferrer\">xylitol</a> on oral health. Studies have shown that oral products with xylitol in them have been <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4232036/\" rel=\"nofollow noreferrer\">\"observed to be effective in preventing caries\"</a> (cavities). These oral products include xylitol chewing gum, xylitol gummy bear snacks, xylitol mouth rinse, and xylitol toothpaste.</p>\n\n<p>According to a medical article published in 2014, on <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4232036/\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4232036/</a> it says regarding xylitol:</p>\n\n<blockquote>\n <p>\"The predominant modality for xylitol delivery has been chewing gum. Chewing gum accelerates the processes of rinsing away acid and uptake of beneficial calcium phosphate molecules to remineralize tooth enamel.\"</p>\n</blockquote>\n\n<p>It also says:</p>\n\n<blockquote>\n <p>\"A study among Montreal children showed that children who chewed xylitol gum had significantly lower caries progression after 24 months than those who did not use gum. These children exhibited a significantly higher number of reversals of carious lesions than the control group, suggesting that remineralization has occurred.\"</p>\n</blockquote>\n\n<p>It also talks about xylitol syrup:</p>\n\n<blockquote>\n <p>\"Twice-daily administration of xylitol oral syrup at a total daily dose of 8 g was observed to be effective in preventing caries.\"</p>\n</blockquote>\n\n<p>Regarding xylitol toothpaste, it says:</p>\n\n<blockquote>\n <p>\"Toothpaste with xylitol led to a decrease in S. mutans colonies in saliva, the amount of secreted saliva, and the increase of pH value. It has a positive effect on the quality of the oral environment and it would be useful introducing it into prophylactic programmes.\"</p>\n</blockquote>\n\n<p>The study concludes that:</p>\n\n<blockquote>\n <p>\"...more research is needed on the mechanisms of action of xylitol...\"</p>\n</blockquote>\n\n<p>and </p>\n\n<blockquote>\n <p>\"While these issues of xylitol still need to be expanded, the benefits it offers are literally worth salivating over.\"</p>\n</blockquote>\n\n<p>Please read the <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4232036/\" rel=\"nofollow noreferrer\">full article</a> for all the details. </p>\n\n<p>An additional medical article from <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/14700079\" rel=\"nofollow noreferrer\">https://www.ncbi.nlm.nih.gov/pubmed/14700079</a> notes that they did a study where samples were soaked in xylitol solution, and says that:</p>\n\n<blockquote>\n <p>\"These results indicate that xylitol can induce remineralization of deeper layers of demineralized enamel by facilitating Ca2+ movement and accessibility.\"</p>\n</blockquote>\n\n<p>Xylitol is a sugar substitute, with 40% less calories and 75% less carbohydrates (<a href=\"https://xylitol.org/xylitol-uses/nutritional-benefits-of-xylitol/\" rel=\"nofollow noreferrer\">than sugar</a>), that <a href=\"https://xylitol.org/xylitol-artificial-natural/\" rel=\"nofollow noreferrer\">naturally occurs in fruits and vegetables</a>, which doesn't have the <a href=\"https://en.wikipedia.org/wiki/Aspartame#Headaches\" rel=\"nofollow noreferrer\">negative side effects reported from many artificial sweeteners</a>. </p>\n\n<p>Xylitol chewing gum, mints, mouth rinse can be found at many stores but are especially prevalent in many health food stores.</p>\n\n<p>This answer wasn't meant to replace any recommendations from a dentist, and was only intended to point out some newer things to possibly supplement your usual oral care. You should probably consult a dentist, if you think you have a cavity.</p>\n", "score": 1 } ]
924
How to stop or even reverse cavities?
[ "dentistry" ]
<p>This is not a question that requires any knowledge of dentistry. All I ask for is your personal experience.</p> <p>What do you in case of a cavity and don't want to go dentist because you fear the side effects of drilling?</p>
8
https://medicalsciences.stackexchange.com/questions/932/can-electroconvulsive-therapy-help-us-to-forget-our-memories
[ { "answer_id": 935, "body": "<blockquote>\n <p>Is it possible to forget our past(bad memories) through Electroconvulsive Therapy?</p>\n</blockquote>\n\n<p>No.</p>\n\n<p>To simplify somewhat, ECT <em>is</em> associated with:</p>\n\n<ul>\n<li>immediate general cognitive and memory dysfunction represented by disorientation (e.g. \"Where am I? Why am I here? What's the date today?\"): transient and generally resolves in a matter of 30-60 minutes after the procedure.</li>\n</ul>\n\n<p>ECT <em>is often</em> associated with:</p>\n\n<ul>\n<li>loss of short-term memory during the period of time that you are having ECT treatments (e.g. \"Did I have lunch already? I saw you today? What did I say?\": Your ability to remember new information will generally return to your normal level within a few weeks to a few months after the treatments are finished.</li>\n</ul>\n\n<p>ECT <em>is sometimes</em> associated with: </p>\n\n<ul>\n<li>memory loss for past events. Events of 2-6 weeks before treatment are the more sensitive. Some patients have \"spotty\" memory loss for events as far back as 6 months before beginning ECT. (\"I can remember Christmas with my family, but I can't remember what gifts I got.\" \"I remember going to New York, but I don't remember where I stayed.\" This memory impairment is <em>potentially</em> (not certainly) permanent. <em>Rarely</em>, patients have reported a more severe memory loss of events which date back further than the 6 months preceding ECT treatments.</li>\n</ul>\n\n<p>You can't count on ECT for <em>any</em> memory loss, since the norm is to remember everything within a few months at most. Also, as mentioned in comments, there is no way to know which memories will be affected. You might remember every painful detail of the past year, and forget some of the more pleasant ones.</p>\n\n<p><sub><a href=\"http://www.nlm.nih.gov/medlineplus/ency/article/007474.htm\" rel=\"nofollow\">Electroconvulsive therapy</a></sub></p>\n", "score": 7 } ]
932
CC BY-SA 3.0
Can ElectroConvulsive Therapy help us to forget our memories?
[ "brain", "depression", "cognitive-science" ]
<p>I need to know whether a person can get rid of his/her past(need selective memory loss) say 5-6 months through ElectroConvulsive Therapy. Otherwise the question can be posed as "Can the ElectroConvulsive Therapy take out a person's memory?"</p> <p>If yes, how far is that possible?</p> <p>If ECT can cause memory loss, explain it in detail</p>
8
https://medicalsciences.stackexchange.com/questions/954/is-it-okay-to-make-a-child-drink-alcohol-when-they-have-a-cold
[ { "answer_id": 958, "body": "<p>The right amount is none. Not at all. Don't do it. Don't even consider it.</p>\n\n<p>There have been multiple studies on alcohol and brain development, quite a few of them on teens, as they are one of the higher risk groups. All of these show significant impacts on brain and social development. There are fewer on the young child (non infant) as they are not considered a risk group. More studies in that area look at the effect of the adults consumption around them.</p>\n\n<p>However, studies such as <a href=\"http://www.sciencedirect.com/science/article/pii/074183299090070S\" rel=\"noreferrer\">this one on postnatal rats</a> show that even a single day of alcohol exposure is enough to affect brain weight and development in the postnatal period. <a href=\"http://www.sciencedirect.com/science/article/pii/0741832994900566\" rel=\"noreferrer\">This study</a> also suggests that once the brain is formed, and going through differentiation (The process by which cells become specialized for their various functions) alcohol has a greater impact than when it is forming in utero.</p>\n\n<p>In short, children should not be given alcohol for any reason. There are now warnings about such medications as cough syrups to not use them for any children under 4, as well as warnings about alcohol in formulas for older kids. I encourage you to read the labels, and choose non alcohol formulas if you do choose to administer cough syrup.</p>\n", "score": 5 } ]
954
CC BY-SA 3.0
Is it okay to make a child drink alcohol when they have a cold?
[ "alcohol", "pediatrics" ]
<p>I've seen a few people make their child drink alcohol when they have a cold. They believe that it can reduce the cold and cough. Is that true? If so, what is the right amount of alcohol the child can consume? In the case of my question, the child is 9 years old.</p>
8
https://medicalsciences.stackexchange.com/questions/1002/effects-of-commuting-on-health
[ { "answer_id": 4215, "body": "<p>When studied from a physiological point of view, commuting is generally divided into two categories: active and non-active. The former involves modes of transportation such as walking and bicycling, where the commuter is actively getting exercise. The latter involves modes of transportation such as cars, buses, and trains, where the commuter is getting virtually no exercise.</p>\n\n<p>Many studies compare modes of transportation that fall into different categories; I chose to put them into one or the other based on which mode was focused on more. Other studies focused solely on one type of commuting. If you want to skip the specifics, you can go all the way to the bottom.</p>\n\n<p><strong>Studies on active commuting</strong></p>\n\n<ul>\n<li><strong><a href=\"http://www.sciencedirect.com/science/article/pii/S0091743507000989\" rel=\"nofollow noreferrer\">Hammer &amp; Chida (2008)</a>:</strong> Commuting involving walking and bicycling corresponded to a reduction in the risk of cardiovascular diseases by approximately 11%. The effect was, for unknown reasons, more pronounced among women than among men.</li>\n<li><strong><a href=\"http://www.bmj.com/content/343/bmj.d4521.full\" rel=\"nofollow noreferrer\">Rojas-Rueda et al. (2011)</a>:</strong> Bicyclists using a bicycle-sharing program avoided ~12.28 deaths in Barcelona over the course of one year. Some of this came from a reduction in road accidents, while other parts of it came from a reduction in carbon dioxide emissions, which reduces air quality in urban areas for commuters.</li>\n<li><p><strong><a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2483568/\" rel=\"nofollow noreferrer\">Davison et al. (2008)</a>:</strong> Children who walk and bicycle to school have, on average, better health than children who take buses or cars to school. Active transport burned 33.2-44.2 kcal per day, assuming a mean travel time for these children at about twenty minutes. Boys were more strongly effected by girls (drastically, in some cases).</p>\n\n<p>Links between different types of commuting and body mass index (BMI) were tenuous at best. However, cardiovascular health was clearly raised among active commuters.</p></li>\n<li><strong><a href=\"http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0838.1991.tb00288.x/abstract\" rel=\"nofollow noreferrer\">Oja et al. (1991)</a>:</strong> Individuals who walk and bicycle for commuting have better cardiorespiratory health. However, cyclists had better health than walkers.</li>\n<li><strong><a href=\"https://www.researchgate.net/profile/Ralph_Buehler/publication/45721029_Walking_and_cycling_to_health_a_comparative_analysis_of_city_state_and_international_data/links/0fcfd50c0b88ca4fe7000000.pdf\" rel=\"nofollow noreferrer\">Pucher et al. (2010)</a>:</strong> Health effects of commuting were studied at the city, county and state levels. Active commuting lead to a greatly lowered risk of obesity and diabetes, while improving overall cardiovascular health.</li>\n<li><strong><a href=\"http://www.jstor.org/stable/27822995?seq=1#page_scan_tab_contents\" rel=\"nofollow noreferrer\">de Hartog et al. (2011)</a>:</strong> This study took into account the potential for traffic accidents when studying commuting cyclists. It was found that the health gains far outweighed the losses from air pollution and accidents.</li>\n</ul>\n\n<p><strong>Studies on non-active commuting</strong></p>\n\n<ul>\n<li><strong><a href=\"http://www.sciencedirect.com/science/article/pii/S135223100700698X\" rel=\"nofollow noreferrer\">Nieuwenhuijsen et al. (2007)</a>:</strong> Particulate matter is abundant many metro systems (London's in particular was studied). While this may not pose a large health threat, it nonetheless may have ill effects.</li>\n<li><strong><a href=\"http://ehp.niehs.nih.gov/0901622/\" rel=\"nofollow noreferrer\">Zuurbier et al. (2010)</a>:</strong> Levels of exposure to air pollution varied with route, vehicle type, and fuel. Commuters on diesel buses were exposed to higher levels of particles than commuters on electric buses. This is in part because \"self-pollution\" from buses contributes a substantial fraction of all inhaled particles. However, cyclists, too, were exposed to high levels of air pollution.</li>\n<li><strong><a href=\"http://www.sciencedirect.com/science/article/pii/S1352231002006878\" rel=\"nofollow noreferrer\">Chan et al. (2002)</a>:</strong> Transportation modes of subways, air-conditioned buses, non-air-condition buses, and taxis were studied. Commuters in non-air-conditioned buses were exposed to more particles, while commuters in subways were exposed to substantially fewer. Driving time did not seem to effect exposure.</li>\n</ul>\n\n<p><strong>Studies on general commuting</strong></p>\n\n<ul>\n<li><p><strong><a href=\"http://bmcpublichealth.biomedcentral.com/articles/10.1186/1471-2458-11-834\" rel=\"nofollow noreferrer\">Hansson et al. (2011)</a>:</strong> The study cites previous studies that have shown commuting to raise stress levels under certain conditions (e.g. long travel times and crowded places). Examples are <strong><a href=\"http://www.ncbi.nlm.nih.gov/pubmed/16719613?dopt=Abstract\" rel=\"nofollow noreferrer\">Evans &amp; Wener (2006)</a></strong> and <strong><a href=\"http://www.sciencedirect.com/science/article/pii/S0272494406000636\" rel=\"nofollow noreferrer\">Evans &amp; Wener (2007)</a></strong>. Other, more complicated, effects have been observed, including loss of sleep and an increase in sick leave.</p>\n\n<p>The study itself followed the population of the county of Scania, in southern Sweden. Commuters had been sent surveys that covered a variety of issues, including stress and mental health. Some correlations were found between demographics and modes of transport (which was to be expected), which most likely influenced the results. The authors found that, in general, commuters had worse sleep and lower energy. Mental health did not appear to be related. </p>\n\n<p>However, given that the results were self-reported, only 56% of people responded to the survey, and there were patterns between various demographics and modes of transportation, the results are not conclusive, even given the vast number of individuals studied. Other effects may have had significant impacts.</p></li>\n<li><strong><a href=\"http://www.sciencedirect.com/science/article/pii/S0167629611000853\" rel=\"nofollow noreferrer\">Roberts et al. (2011)</a>:</strong> Commuting can have negative psychological effects in women, while those same effects are not visible in men.</li>\n<li><strong><a href=\"http://journals.lww.com/epidem/Abstract/2011/03000/Respiratory_Effects_of_Commuters__Exposure_to_Air.13.aspx\" rel=\"nofollow noreferrer\">Zuurbier et al. (2011)</a>:</strong> Commuters using active and passive transport may be exposed to higher levels of particulate matter from air pollution. This may cause low-level respiratory effects.</li>\n<li><strong><a href=\"http://www.sciencedirect.com/science/article/pii/S1352231011002299\" rel=\"nofollow noreferrer\">Knibbs et al. (2011)</a>:</strong> Different modes of transportation for commuters lead to different levels of exposure to particles in the air. From least exposure to most exposure, the results were: bicycle, bus, automobile, rail, walking, and ferry. This shows a significantly higher exposure among walkers than among cyclists, meaning that active transport is not necessarily better than passive transport in this respect.</li>\n</ul>\n\n<hr>\n\n<p><strong>Summary</strong></p>\n\n<p>Cardiovascular health from exercise and exposure to air pollution are the two main effects of commuting, although commuting may have minor effects on stress and mental health. Cyclists and walkers had much better cardiovascular health than non-active commuters in cars, buses, trains, and subways. This may lead to lower risks of obesity and diabetes.</p>\n\n<p>Exposure to air pollution varied. Commuters using the subways were exposed to different levels of different air particles than aboveground commuters. Commuters in some buses were exposed to high levels of air pollution; however, walkers and cyclists were exposed to high(er) levels in some cases. This exposure can lead to respiratory problems, although this has not yet been studied in great detail.</p>\n", "score": 9 } ]
1,002
CC BY-SA 3.0
Effects of commuting on health
[ "lifestyle", "travel" ]
<p>I've been trying to figure out whether or not my commute may be affecting my health in a major way. Does commuting have an effect on health in any way? If so, does it matter how long the commute is, what kind of transportation (bus, train, or car), or the time of day when commuting?</p> <p>I tried googling this but while I found several news articles, I haven't found links to studies and solid research.</p>
8
https://medicalsciences.stackexchange.com/questions/1014/do-we-have-a-general-system-of-class-of-drugs-that-a-layman-can-understand
[ { "answer_id": 1015, "body": "<p>There is no need for any person to learn any drug taxonomy, unless this person is creating or extensively using clinical or pharmacological documentation. I don't doubt that somewhere, a single unified taxonomy of drugs exists, prescribed by some standardization body - and I also don't doubt that it's a major pain to use and as hated by physicians as ICD-10. </p>\n\n<p>For all medical purposes outside of documentation, people use <a href=\"http://www.amazon.de/Women-Fire-Dangerous-Things-Categories/dp/0226468046\">categorization</a> the same way they do it for all other concepts in their life. They put a label on any group they (and hopefully their communication partner) readily recognize. And what they recognize depends on their level of expertise in the field. </p>\n\n<p>This is why you, the patient, will naturally say \"drugs for <a href=\"http://en.wikipedia.org/wiki/Migraine\">migraine</a>\" while talking to a friend of physician. A physician will use categories such as \"<a href=\"http://en.wikipedia.org/wiki/Serotonin_receptor_agonist\">serotonin receptor agonists</a>\". Neither of you two studied a taxonomy tree of drugs before using a correct category name. You knew \"there are migraines\" and derived a proper category name from it. The physician learned about the role of serotonin in the brain, and one chapter of his textbook explained how serotonin is connected to migraine, and another explained how there are drugs which mimic the effects of serotonin by activating the same receptors which are usually activated by serotonin, so they can stop a migraine. </p>\n\n<p>Note that the two categories are not the same, even though they have some overlap. Some serotonin receptor agonists are a type of migraine drugs. But there are migraine drugs which are not serotonin receptor agonists, and there are serotonin receptor agonists which do something other than heal migraine, because they activate a slightly different set of serotonin receptors. But there is no simple way to translate the category \"serotonin receptor agonists\" to layman's terms. It's not even a matter of it resulting from too detailed criteria, and saying that it's good for a layman to learn the more general category above it - because the more general category of \"receptor agonist\" is not easier to understand. <a href=\"http://rads.stackoverflow.com/amzn/click/1591842948\">Experts' taxonomies are not simply more detailed versions of a layman's taxonomy of the same area, they are orthogonal to laymen taxonomies, because they are based on completely different principles.</a> </p>\n\n<p>If what you want is a categorization system reflecting your current knowledge, then you already have it. Talking about \"drugs for fever\" or \"drugs for migraine\" is not wrong in any way. Just say whatever you mean when you need it. There could be a category which you need to talk about but cannot come up with a succinct name for it, such as \"drugs for fever which are safe for toddlers and are taken through the mouth\" - but it is unlikely that it already makes a node in somebody else's standardized taxonomy, you have to describe it. And while your doctor might be inclined to use the description \"pediatric oral antipyretic\" instead, this does not make your label less valid. </p>\n\n<p>If you want to be able to work with a more intricate taxonomy, you'll need more medical knowledge. And that's great - everybody can use knowledge about such an important subject. But in this case, the knowledge comes first. Using the correct taxonomy will come naturally, as a byproduct of your increased knowledge. The other way round does not work. </p>\n\n<p>Of course, it can happen that you come across information which refers to a category you don't understand, for example in the list of interactions of a drug you are taking. But if you want to understand this information, the way is not through some special taxonomy (which cannot be mapped to concepts you already know anyway). If you really need to know what makes a class of drug a \"class\" and not a random collection of drugs, and a source you find does not explain it in terms you understand, you need another source which will try to explain the criteria behind the existing expert's category. I'm sure the users of this site will be happy to help you in this, too. </p>\n", "score": 12 }, { "answer_id": 1407, "body": "<p>I second rumstscho's answer (except the part about ICD-10 being a major pain to use).</p>\n\n<p>There is a classification system of medicines that is quite detailed and widely used, and it is called:</p>\n\n<h2>Anatomical Therapeutic Chemical (ATC) classification system</h2>\n\n<p>As you can guess from the name it classifies medicines based on: </p>\n\n<ul>\n<li>the organ or system on which they act and</li>\n<li>their therapeutic properties and</li>\n<li>pharmacological properties and</li>\n<li>chemical </li>\n</ul>\n\n<p>How do they take all of these into account? By using a <strong>multilevel</strong> classification system. The classification is paired with a code system, which can be used to search for a medicine on a regulatory agency's website, for instance.</p>\n\n<p>ATC classification system has five levels: </p>\n\n<p><strong>First level</strong> - <a href=\"https://en.wikipedia.org/wiki/Anatomical_Therapeutic_Chemical_Classification_System\" rel=\"nofollow\">anatomical main group</a> (this is a level a layperson can easily understand)</p>\n\n<blockquote>\n <p>A Alimentary tract and metabolism</p>\n \n <p>B Blood and blood forming organs</p>\n \n <p>C Cardiovascular system</p>\n \n <p>D Dermatologicals</p>\n \n <p>G Genito-urinary system and sex hormones</p>\n \n <p>H Systemic hormonal preparations, excluding sex hormones and insulins</p>\n \n <p>J Antiinfectives for systemic use</p>\n \n <p>L Antineoplastic and immunomodulating agents</p>\n \n <p>M Musculo-skeletal system</p>\n \n <p>N Nervous system</p>\n \n <p>P Antiparasitic products, insecticides and repellents</p>\n \n <p>R Respiratory system</p>\n \n <p>S Sensory organs</p>\n \n <p>V Various</p>\n</blockquote>\n\n<p><strong>Second level</strong> - therapeutic main group (this is a level that an informed patient can understand - if you are somewhat familiar with the medical condition/indication the medicine is for, you can understand this level)</p>\n\n<p><strong>Third level</strong> - therapeutic/pharmacological subgroup (this is where things get quite technical; these waters are generally too deep for a layperson)</p>\n\n<p><strong>Fourth level</strong> - chemical/therapeutic/pharmacological subgroup</p>\n\n<p><strong>Fifth level</strong> - the chemical substance</p>\n\n<p>How are medicines included in the system:</p>\n\n<blockquote>\n <p><em>Inclusion and exclusion criteria\n The WHO Collaborating Centre in Oslo establishes new entries in the ATC classification on requests from the users of the system. These include manufacturers, regulatory agencies and researchers. The coverage of the system is not comprehensive. A major reason why a substance is not included is that no request has been received.</em> [...]</p>\n \n <p><em>Complementary, homeopathic and herbal traditional medicinal products are in general not included in the ATC system.</em></p>\n</blockquote>\n\n<p>from: <a href=\"http://www.whocc.no/atc/structure_and_principles/\" rel=\"nofollow\">WHO Collaborating Centre for Drug Statistics Methodology</a></p>\n\n<p>(if you are really interested in this subject, you might find some chapters of <a href=\"http://www.whocc.no/filearchive/publications/1_2013guidelines.pdf\" rel=\"nofollow\">this publication</a> interesting. </p>\n\n<hr>\n\n<p>However, there is no need for you to learn this (or any other classification). If your goal is to gain knowledge on medicines the area you are interested in is <a href=\"https://en.wikipedia.org/wiki/Pharmacology\" rel=\"nofollow\">pharmacology</a> or more precisely <a href=\"https://en.wikipedia.org/wiki/Pharmacodynamics\" rel=\"nofollow\">pharmacodynamics</a>. This is quite a large area, but a real catch for a layperson is that it is an applied science, sou you would need knowledge from physiology, patophysiology and medicinal biochemistry first; and for those you would need cell biology, some anatomy and histology, microbiology, biochemistry (for which you definitely need some chemistry)... This would be a few year's quest and you would still need a curriculum and someone to supervise your learning process to make sure you understand all important concepts correctly. </p>\n\n<p>This doesn't mean that you can't be a well informed, educated patient (or patient's caregiver, family member). You just don't need to learn about all of the major illnesses and medicines. Simply, when (if) a health problem occurs focus your efforts on that specific area. You cannot and should not use the knowledge you gain to self-medicate; it should serve you to communicate better with your health care providers, participate in the decisions, and if necessary consider if it's time to get a second opinion on something.</p>\n\n<hr>\n\n<p>An aside: <a href=\"https://books.google.rs/books?id=s2R-ZYz_iBYC&amp;printsec=frontcover&amp;dq=%22rang+and+dale+pharmacology%22+%22table+of+contents%22&amp;hl=en&amp;sa=X&amp;ei=UhCQVen4JIX5UP66g_AC&amp;redir_esc=y#v=onepage&amp;q=%22rang%20and%20dale%20pharmacology%22%20%22table%20of%20contents%22&amp;f=false\" rel=\"nofollow\">Here is an example</a> of how a book in pharmacology is organised. The lessons about specific medicines start from section 2. You can see that sometimes a cellular/chemical mechanism is used (section 2), and sometimes a whole organ or system of organs (section 3 and 4) or the disease to be treated (section 5 and chapters 43-45 in section 4 e.g.) (whichever is better to explain how a certain medicine works). I do not recommend this book for you (not that it's not good, it's a great one) - because it's designed for grad students of medicine/pharmacy as well as phd students. While it is great because it encourages critical thinking, you can get lost in the quantity of details. I've just used its table of contents as an example how one can go about studying pharmacology. For a layperson I'd say that <strong>starting</strong> with Wikipedia is not a bad thing (articles there are usually well organised), as long as you make sure to check the accuracy of information you find there. </p>\n", "score": 4 } ]
1,014
CC BY-SA 3.0
Do we have a general system of class of drugs that a layman can understand?
[ "medications" ]
<p>When I was reading the accepted answer in the <a href="https://health.stackexchange.com/a/307/99">Why do doctors prescribe steroid tablets even though they know the side effects?</a> question, I noticed this phrase located in the second paragraph:</p> <blockquote> <p>...if there is a single <strong>class of drugs</strong>...</p> </blockquote> <p>I wonder what class of drugs we have. So I started researching and got to the <a href="http://www.drugs.com/drug-classes.html" rel="nofollow noreferrer">Drug Classes</a> page on Drugs.com. But I don't understand a word. And even if I can understand them, there are so many classes that I cannot remember them all. Do we have another class system that is more general and less number of classes? If there is not, which classes should I know as a layman?</p> <p><strong>Clarification</strong>: while I know nothing about medical, in my high school I used to study natural sciences very well, which include biology and chemistry.</p>
8
https://medicalsciences.stackexchange.com/questions/1037/does-bmr-adjust-and-decrease-in-response-to-calorie-restriction-diets
[ { "answer_id": 1062, "body": "<p>First of all, the 1000-2500 calorie statement <a href=\"https://health.stackexchange.com/questions/981/does-it-become-harder-to-lose-weight-as-you-age/1011#1011\">from the answer to this question</a> is not due to formula inaccuracies (only 0.5% of the variation were attributed to that), but is the <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/16280423\" rel=\"nofollow noreferrer\">actual measured BMR in a study within Scottish population</a>.</p>\n\n<p>Second, we know from the above mentioned question in SE that the BMR is dependent, amongst others, of fat-free body mass (FFM), i.e. muscle mass. In the forementioned study, 63% of BMR variation could be attributed to variations in FFM. And we also know that <a href=\"http://link.springer.com/article/10.2165/00007256-200636030-00005\" rel=\"nofollow noreferrer\">diets can lead to a loss of this mass, if they aren't overcompensated by exercise; thus the logical deduction can be made that a diet can lead to BMR decrease, if it's not compensated for</a>, e.g. by exercise or high-protein-intake diets.</p>\n\n<p>I couldn't find any other evidence on direct changes to BMR by a diet, so this connection (diet - FFM decrease - BMR decrease) may just be it for now.</p>\n", "score": 7 }, { "answer_id": 1109, "body": "<p>Yes it can. As a general statement, I'm not sure how much it can go down before it's a problem, which is what I think you are asking as your second question. Starving to death might be seen as this taking the BMR close to zero (though I don't think you would get to zero before death).</p>\n\n<p>I think a good reference for this is Peter Emery's review article \"<a href=\"http://www.nature.com/eye/journal/v19/n10/full/6701959a.html#bib14\" rel=\"nofollow\">Metabolic changes in malnutrition</a>.\" There may be more appropriate references when concerning elective reductions in caloric intake, but I suspect the results are <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/1885261\" rel=\"nofollow\">similar</a> on a smaller scale.</p>\n\n<p>There are a few sections of the review that are worth quoting and discussing here:</p>\n\n<p>First the general trend and cause:</p>\n\n<blockquote>\n <p>The basal metabolic rate actually increases during the first few days\n of starvation, under the influence of catecholamines that are secreted\n in response to decreasing blood glucose concentrations. This\n probably reflects the high rate of gluconeogenesis that occurs at this\n time. As fasting progresses, however, metabolic rate decreases as free\n T3 and catecholamine levels decrease and the rate of gluconeogenesis\n decreases.</p>\n</blockquote>\n\n<p>In essence, when you first start to fast (the references<a href=\"http://www.ncbi.nlm.nih.gov/pubmed/2405717?dopt=Abstract&amp;holding=npg\" rel=\"nofollow\"> [1</a>,<a href=\"http://www.ncbi.nlm.nih.gov/pubmed/10837292?dopt=Abstract&amp;holding=npg\" rel=\"nofollow\">2] </a>that the review sites are from 1-4 days in this section) the body looks to other sources of energy (<a href=\"https://en.wikipedia.org/wiki/Gluconeogenesis\" rel=\"nofollow\">gluconeogenesis</a>). That is not sustainable over time, and then the BMR begins to drop. How it begins to drop is largely through the lost of lean tissue, with a focus on muscle mass, which is probably a good evolutionary choice over more important systems such as the brain:</p>\n\n<blockquote>\n <p>The response to a less severe degree of food restriction can also be\n seen as a series of adaptive processes with the same priorities, that\n is to maintain the supply of glucose to the brain and to minimise the\n loss of lean tissue. Basal metabolic rate decreases to minimise the\n negative energy balance. This is achieved partly by loss of\n metabolically active tissue, but there is also some evidence that the\n efficiency of energy metabolism increases leading to a decrease in\n energy expenditure per unit cell mass.</p>\n</blockquote>\n\n<p>Again, the <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/10365978?dopt=Abstract&amp;holding=npg\" rel=\"nofollow\">referenced review article</a> is also worth a read, especially as it deals with otherwise healthy individuals and people \"dieting\" in the common sense of the word (but in no means the medical). Again body composition and physical activity take a leading role here, but changes in efficiency are certainly noted if not understood. A conclusion reached on efficiency calculation (<a href=\"http://www.ncbi.nlm.nih.gov/pubmed/10365978?dopt=Abstract&amp;holding=npg\" rel=\"nofollow\">ibid</a>) is also worth quoting:</p>\n\n<blockquote>\n <p>It would thus appear that the generally used indicator of metabolic\n efficiency in humans, that is a reduced oxygen consumption per unit\n fat free mass, is fraught with problems since it does not account for\n variations in contributions from sub-compartments of the fat free mass\n which include those with high metabolism at rest such as brain and\n viscera and those with low metabolism at rest such as muscle mass.</p>\n</blockquote>\n\n<p>When in your life span you start on your low caloric diet can effect the outcome of the diet. A commonly understood example is a shorter stature/smaller skeletal frame will develop under limited nutritional intake. It's probably worth noting that on an evolutionary scale, having too many calories is an exceedingly new problem. In other words, even if we wouldn't see it as preferential in the developed world today, it is probably an adaptive response to lose lean body mass or not develop additional skeletal structure (with goals of efficiency). </p>\n\n<p>I will end returning <a href=\"http://www.nature.com/eye/journal/v19/n10/full/6701959a.html#bib14\" rel=\"nofollow\">Dr. Emery's</a> coverage of the same topic:</p>\n\n<blockquote>\n <p>The main response in chronically malnourished populations is slow\n growth rate, delayed maturity, and small adult stature. Small stature\n can be seen as a successful adaptation to low-energy intake because\n overall basal metabolic rate will be low. However, when metabolic rate\n is adjusted for fat-free mass there is no significant difference\n between those who are most malnourished and those who are well\n nourished. The reason for this is that the main deficit in lean\n tissue mass is in muscle, which has a relatively low metabolic rate,\n while the size of the visceral organs, which are much more\n metabolically active, is much less affected. Hence these changes in\n body composition may cancel out any increase in the efficiency of\n cellular metabolism.</p>\n</blockquote>\n", "score": 4 } ]
1,037
CC BY-SA 3.0
Does BMR adjust and decrease in response to calorie restriction diets?
[ "diet", "lasting-effects-duration", "measurement", "calories" ]
<p>Is it possible for your Basal Metabolic Rate (BMR) to adjust in response to dieting for long periods of time? If this does happen how much can it go down? I have heard that BMR ranges from 1000 - 2500 calories. Assume that multivitamins and other nutritional supplements (calcium, magnesium, minerals) are taken.</p>
8
https://medicalsciences.stackexchange.com/questions/1039/can-someone-explain-these-cancer-names
[ { "answer_id": 1043, "body": "<p>The causal sequence indicated here doesn’t make a lot of sense to me. Having signed many death certificates, I can sympathize with the doctor who signed off on it. Generally, these have to be typed up in <a href=\"http://www.cdc.gov/nchs/data/dvs/death11-03final-acc.pdf\">a form</a> (in my experience, on a typewriter....). Someone other than the doctor usually does that, which means there is some verbal communication between the doctor and an administrative person about what should go in the blanks and... it doesn’t always come out exactly perfectly. </p>\n\n<p><a href=\"http://www.mayoclinic.org/diseases-conditions/colon-cancer/basics/definition/con-20031877\">Colon carcinoma</a> is generally used to indicate a <em>primary</em> tumor of the epithelial cells of the colon. That is, the cells lining the inside of the colon underwent a mutation of some sort that caused a cancerous growth. </p>\n\n<p>Abdominal carcinomatosis is what happens when cancer cells fall off (basically) the tumor and “seed” the <a href=\"https://www.dartmouth.edu/~humananatomy/part_5/chapter_26.html\">peritoneal space</a>, which is the area outside the gut but inside the abdomen. The cells land in various places and start growing more tumors. Often, this is accompanied by secretion of fluid which results in <a href=\"http://emedicine.medscape.com/article/170907-overview\">ascites</a>, and the cancer can also spread by falling into this fluid and landing elsewhere. </p>\n\n<p><a href=\"http://www.cancer.gov/about-cancer/what-is-cancer/metastatic-fact-sheet\">Metastatic carcinoma</a> (here to lung and liver) is what happens when the cancer cells get in the bloodstream or lymphatic system and spread to ‘distant’ organs. There they set up new tumors, but the cells can still be identified as having originated from the colon. </p>\n\n<p>The causal sequence is then: </p>\n\n<blockquote>\n <p>colon carcinoma &#8594; abdominal carcinomatosis<br>\n colon carcinoma &#8594; metastatic carcinoma (sites: liver and lung)</p>\n</blockquote>\n\n<p>Generally it would also be possible to state a more proximate factor that directly resulted in death. For cancer metastatic to lung, that might be ‘hypoxemic respiratory failure’ (lack of oxygen).</p>\n\n<p>One way to indicate that on a <a href=\"http://www.cdc.gov/nchs/data/dvs/death11-03final-acc.pdf\">death certificate</a> would be;</p>\n\n<pre><code> PART I. Enter the chain of events.....:\n\n Hypoxemic respiratory failure \n due to (or as a consequence of): \n Metastatic Liver and Lung Carcinoma\n due to (or as a consequence of): \n Colon carcinoma \n\n PART II. Enter other significant conditions contributing to death....:\n\n Abdominal carcinomatosis \n</code></pre>\n", "score": 6 } ]
1,039
CC BY-SA 3.0
Can someone explain these cancer names?
[ "cancer", "terminology" ]
<p>I am looking at the death certificate of a relative, and I do not understand these names.</p> <pre><code>Colon Carcinoma due to or as a consequence of Abdominal Carcinomatosis due to or as a consequence of Liver &amp; Lung Metastatic Carcinoma </code></pre> <p>Thanks!</p>
8
https://medicalsciences.stackexchange.com/questions/1063/sleeping-on-stomach-why-are-people-naturally-drawn-to-it-if-its-bad
[ { "answer_id": 1923, "body": "<p>Sleeping in a prone position is not bad. However there are some complications of it that can be negative. A simple example is drooling. A more important problem with sleeping in a prone position is poor posture. Most people don't have a bed like a chiropractic table that allows them to breathe with their face straight down while maintaining a neutral spine. Due to this lack of beds designed for the prone sleeper they have to turn their head to the side. This extreme rotation held for 8 hours can cause neck pain. Most people who sleep that way also use a pillow under their head and/or upper body causing excessive and prolonged lumbar extension. This can lead to low back pain. <a href=\"http://www.acatoday.org/JacaDisplay1.cfm?CID=4488&amp;DisType=PDF\" rel=\"noreferrer\">J Amer Chiropr Assoc 2011 May-June;48(4):17-18</a></p>\n\n<p>The textbooks and the research I've seen always say the best sleep position maintains a neutral spine. That means on your back with a pillow supporting your neck and one supporting your knees. Alternatively you can sleep on your side with a pillow supporting your neck, head, and the top arm as well as a pillow between the knees. This will keep the spine in a neutral position. I always tell my patients that the best way to sleep is the one that gives you a good, full nights sleep. You can probably improve your sleep with a few modifications, but if you are a side sleeper, you'll have a difficult time trying to force yourself to your back because, you're not conscious at the time. The Mayo Clinic has some excellent <a href=\"http://www.mayoclinic.org/diseases-conditions/back-pain/multimedia/sleeping-positions/sls-20076452?s=3\" rel=\"noreferrer\">images</a> that can help with modifications. </p>\n\n<p>People tend to sleep in positions that are comfortable for them. If all day long they sit or work in a flexed posture then their body may crave the extension of their low back that comes from prone positions. In fact they may sleep prone because of back pain caused by excessive flexion. We've all seen this phenomenon before as we squirm in our chair or our legs ache to stretch when on a long flight or car ride. Motion and proper posture affects every aspect of our life. More research can be found <a href=\"http://www.posturezone.com/pages/Resources\" rel=\"noreferrer\">here</a> (No Affiliation).</p>\n", "score": 7 } ]
1,063
CC BY-SA 3.0
Sleeping on stomach - why are people naturally drawn to it if it&#39;s bad?
[ "sleep", "stomach", "back", "position" ]
<p>Why are some adults and children naturally drawn to sleeping on their stomachs if it's not a good sleep position (according to many articles)? I understand it's not good for babies because of the increased SIDS risk, but I think I also recall hearing or reading that it would cause them to sleep deeper than on their back which, aside from SIDS risk, sounds like it has potential to be beneficial for people?</p> <p>EDIT: Here are some example articles which speak negatively about stomach sleeping.</p> <ul> <li><a href="http://www.cnn.com/2011/HEALTH/04/19/healthiest.sleep.position/">http://www.cnn.com/2011/HEALTH/04/19/healthiest.sleep.position/</a></li> <li><a href="http://www.doctoroz.com/article/best-sleep-positions">http://www.doctoroz.com/article/best-sleep-positions</a></li> <li><a href="http://www.mayoclinic.org/diseases-conditions/back-pain/multimedia/sleeping-positions/sls-20076452?s=3">http://www.mayoclinic.org/diseases-conditions/back-pain/multimedia/sleeping-positions/sls-20076452?s=3</a></li> </ul>
8
https://medicalsciences.stackexchange.com/questions/1064/do-vitamins-affect-sense-of-taste
[ { "answer_id": 1067, "body": "<p>So it's important to separate cravings/<a href=\"https://en.wikipedia.org/wiki/Specific_hunger\" rel=\"noreferrer\">specific hungers</a> from <a href=\"https://en.wikipedia.org/wiki/Taste\" rel=\"noreferrer\">taste</a>. </p>\n\n<p>One's body should, to some degree be able to adjust it's specific hungers to meet it's dietary needs. This one area where our larger brains come with a catch 22. While being smarter and aware allows us to feed ourselves better, we also can ignore or improperly process the bodies attempt to control our appetites.</p>\n\n<p>Moving on to taste buds (<a href=\"https://www.ncbi.nlm.nih.gov/pubmed/24287552\" rel=\"noreferrer\">here is a better review than wiki</a>). The average taste bud lasts 8-12 days (<a href=\"https://www.ncbi.nlm.nih.gov/pubmed/24287552\" rel=\"noreferrer\">ibid</a>), so if you're noticing an effect before then, it's probably not related. Also, there development and distribution is associated with genetic and <a href=\"https://en.wikipedia.org/wiki/Epigenetics\" rel=\"noreferrer\">epigenetic</a> factors, not environment and diet.</p>\n\n<p>Instead I think that you are noticing that your taste receptors, like most sensory systems, become less responsive after saturation and repeated stimulation.</p>\n\n<p>If we look at part F of the <a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4345348/\" rel=\"noreferrer\">following figure</a>:</p>\n\n<p><img src=\"https://i.stack.imgur.com/Jabfv.jpg\" alt=\"Choi et al figure 5\"></p>\n\n<p>You will notice how the response of the taste bud to a salty solution decreased significantly after each application (the time between each stimulus was 10 min). Thus something that started as tasty and salty 30 min ago won't by the time you've finished gorging yourself on oranges.</p>\n\n<p>A way to test this at home, <strong>with the extreme caveat that I do not recommend super dosing vitamin C</strong>, would be to try this with a fixed dose (appropate for age and weight) of vitamin C dissolved in water over the same interval you were eating the oranges. I think you will notice little to no change in the taste of the vitamin C unless you are doing it in a very short amount of time.</p>\n", "score": 7 } ]
1,064
CC BY-SA 3.0
Do vitamins affect sense of taste?
[ "nutrition", "micronutrients" ]
<p>I like oranges. I <em>really</em> like oranges. But I go through cycles of eating them. When I start, they are <em>really</em> sweet. By my fifth of the day they have turned quite bitter.</p> <p>Sensing a pattern I have performed an experiment.</p> <p>The theory is that the more vitamin C I eat, the less I want foods that contain vitamin C. So, I stopped eating oranges for a month. I had one orange and it was really sweet - which validates the inverse of my theory (the less vitamin C I eat the more I want foods that contain it).</p> <p>I then started taking vitamin C tablets for a week and had an orange, and it was bitter. To make sure it wasn't just a bitter orange I asked a friend to share it with me (without explaining why I wanted to share the orange with him). He said it was very sweet and enjoyed it loads.</p> <p>I have been unable to locate studies or anecdotes regarding this sort of thing.</p> <p>So, my question:</p> <p>Do our bodies alter our taste buds based on what we eat in order to maintain a stable balance of nutrients, vitamins, etc? (by encouraging/discouraging us to eat food x because we need/don't need the nutrients/vitamins/etc)?</p> <p>I have previously noticed a similar alteration in sense of taste for spinach for a little while. I assume I needed the iron? </p> <p>From an evolutionary point of view this makes sense - as a way of encouraging us to eat what we need to stay healthy.</p>
8
https://medicalsciences.stackexchange.com/questions/1116/whats-wrong-with-fish-canned-in-oil
[ { "answer_id": 1144, "body": "<p>This is most likely referring to the fact that canned fish is often packed in vegetable oils, which add fat content while not providing the omega-3 content of fish oil.</p>\n", "score": 2 } ]
1,116
CC BY-SA 3.0
What&#39;s wrong with fish canned in oil?
[ "diet", "oil", "fish" ]
<p>I found the following post on a food-related forum (<a href="http://www.marksdailyapple.com/forum/thread10121.html#post141067">here</a>):</p> <blockquote> <p>Farmed fish do have omega 3 in them. They have a chunk of omega 6 too so while they do have omega 3, they're not ideal for normalizing the ratio. However there is a case in which sardine flesh is being sold after the omega 3 has been extracted to make sardine oil. A good rule of thumb is that the saturated fat should be about a quarter or less of of the total fat if the tin doesn't specifically say that it has omega 3. If saturated fat is a higher percentage of the sardine, the omega 3 has been removed. Also be wary of fish canned in oil. Bad news!</p> </blockquote> <p>Why should we be wary of fish canned in oil?</p>
8
https://medicalsciences.stackexchange.com/questions/1128/detriments-to-soylent-fad
[ { "answer_id": 1305, "body": "<p>I think the biggest issue (already mentioned by Joshua Frank) is our flawed understanding of how nutrition interacts with human health, especially for the long term. If nutrition were as easy as Soylent claims, well, we could take a multivitamin and eat ice cream for the rest of our lives, no problem. But what do you know, it's more complicated than that. We're constantly discovering new nutrients or new roles for nutrients we already knew about. We now know from microbiome- and psychology- related research that we are not simply the sum of what we eat, but also why we eat and how we eat.</p>\n\n<p>You probably won't die from consuming Soylent (people eat more terrible things all the time), but I wouldn't consider it any healthier than, say, Wonderbread with a multivitamin chaser. In the end, I merely consider it another addition to our supermarkets full of highly processed food.</p>\n\n<p>And dude - it's made of people. Gross.</p>\n", "score": 1 }, { "answer_id": 1324, "body": "<p>The wisest thing ever said on television was in an old margarine commercial: \"It's not nice to fool Mother Nature.\"</p>\n\n<p>Eating Soylent exclusively, or as a high percentage of food intake, is unwise, and the fact that some people seem to be getting away with it, unscathed, should offer little reassurance. As others have remarked, we have no way of knowing if we know all the essential nutrients Mother Nature wants us to have. And we may not ever know, because nutrient deficiencies can take years or decades to appear. Vitamin B12 and vitamin E are examples of this. </p>\n\n<p>I recall one lecturer talk about a vitamin or mineral deficiency that was discovered by medical science only because a woman had habitually eaten nothing but an egg on toast for 20 years (cannot remember what it was). And then there are other deficiencies that have come to light much more recently, when hyperalimentation solutions lacked something that humans had never before suspected was essential (I'm thinking vanadium, but again am not sure).</p>\n\n<p>On top of this, I would additionally be concerned about the very naive medical reasoning that Soylent's inventor evinces. On this page <a href=\"http://robrhinehart.com/?p=424\" rel=\"nofollow\">http://robrhinehart.com/?p=424</a> he wonders if his family's fondness for tomatoes reflects a salutary effect of lycopene peculiar to his family's genetics. Nothing is impossible, of course, but the unstated assumption, which appears often in Soylent discussions, is that human appetite for specific substances is correlated with the body's need for, or benefit from, those specific substances. Although true for calories (we get hungry when deprived of calories), in general it is balderdash -- go read about pica and cissa. (You'll read, for example, about iron deficiency causing a massive craving for ice, which is, of course, iron-free. Iron deficiency also causes craving for tomato seeds, which are poor in iron; maybe the inventor's family is iron deficient.) And then you can go read about B12 deficiency (called pernicious anemia, because it was uniformly fatal). Those people had aversions to meat, when, in fact, meat was the food richest in the nutrient they were missing.</p>\n\n<p>Life is an exceedingly complex and subtle machine, and it's risky to think that humans can re-engineer macro processes that are built into us at the deepest levels. If you consume a lot of Soylent and get a disease unknown to medical science, I will be very happy, because we will have learned something about metabolism, and minimally sad, because it was a choice you didn't have to make.</p>\n", "score": 0 } ]
1,128
CC BY-SA 3.0
Detriments to Soylent fad?
[ "nutrition", "diet" ]
<p>There has been a bit of a <a href="https://www.soylent.com/">soylent</a> fad in my friend group recently. I'm interested in it as an occasional replacement meal. I have noticed that I'm a little more energetic when I do, suggesting I need to change my diet...</p> <p>Still, there are some people who have taken the fad to close to extremes, and seem to be doing okay. There are plenty of "<a href="http://www.theverge.com/2014/7/17/5893221/soylent-survivor-one-month-living-on-lab-made-liquid-nourishment">One</a> <a href="http://motherboard.vice.com/read/soylent-how-i-stopped-eating-for-30-days">Month</a> <a href="http://www.raptitude.com/2014/08/what-happened-during-my-30-days-on-a-liquid-superfood/">Soylent</a> <a href="http://www.raptitude.com/experiment-no-18-a-month-on-soylent/">Challenge</a>" or <a href="http://robrhinehart.com/?p=474">longer</a> blog posts that I've seen in passing, praising and condemning its merits. I know the liquid diet isn't a new thing, but some people claim that just merely by it being liquid has a detrimental effect, others claim that there's no way some miracle food can work.</p> <p>I like variety, but I was wondering if anyone here had more down to earth criticisms. A lot of the anti-soylent things I've seen were mere opinion.</p>
8
https://medicalsciences.stackexchange.com/questions/1133/probiotic-capsule-or-powder
[ { "answer_id": 1153, "body": "<p>I cannot answer your question directly, but explaining some general considerations might help to clarify what would be a sound choosing approach.</p>\n\n<p>When you say:</p>\n\n<blockquote>\n <p><em>In my opinion it is better to use capsule since it will protect the bacteria from the acid environment in the stomach.</em></p>\n</blockquote>\n\n<p>bear in mind that this applies to <strong>gastro-resistant</strong> capsules only:</p>\n\n<blockquote>\n <p><em>Gastro-resistant capsules are delayed-release capsules\n that are intended to resist the gastric fluid and to release\n their active substance or substances in the intestinal fluid.\n Usually they are prepared by filling capsules with granules\n or with particles covered with a gastro-resistant coating or\n in certain cases, by providing hard or soft capsules with a\n gastro-resistant shell (enteric capsules).</em> (<a href=\"http://lib.njutcm.edu.cn/yaodian/ep/EP5.0/07_monographs_on_dosage_forms/Capsules.pdf\" rel=\"nofollow\">Ph.Eur.5.0.</a>)</p>\n</blockquote>\n\n<p>Many manufacturers of probiotics use hard (gelatine) capsules which are not resistant to stomach acid. In fact these two sorts of capsules have to comply with different pharmacopoeial requirements: </p>\n\n<p><em>Gastro-resistant capsules</em>:</p>\n\n<blockquote>\n <p><strong><em>Disintegration</strong>. For capsules with a gastro-resistant shell carry out the test for disintegration [...] use 0.1 M hydrochloric acid as the liquid\n medium and operate the apparatus for 2 h, or other such time as may be authorised, without the discs. Examine the state of the capsules.<strong>The time of resistance to the acid medium</strong> varies according to the formulation of the capsules to be examined. It is typically 2 h to 3 h but even with authorised deviations it <strong>must not be less than 1 h. No capsule shows signs of disintegration or rupture permitting the escape of the contents.</em></strong> (Ph.Eur.5.0)</p>\n</blockquote>\n\n<p>Whereas for <em>hard capsules</em> it says:</p>\n\n<blockquote>\n <p><em>Use water R as the liquid medium. When justified and authorised, 0.1 M hydrochloric acid or artificial gastric juice R may be used as the liquid medium. [...] Operate the apparatus <strong>for 30 min</strong>, unless otherwise justified and authorised and examine the state of the capsules. <strong>The capsules comply with\n the test if all 6 have disintegrated.</em></strong> (Ph.Eur.5.0)</p>\n</blockquote>\n\n<p>Some strains of probiotics are found to be <a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1151822/#r27\" rel=\"nofollow\">acid resistant</a> which can be enhanced by formulation factors other than gastro-resistant coating. On the other hand, manufacturers of probiotics in gastro-resistant capsules often state (on their websites e.g.) that they deliver more units of probiotic bacteria to the intestines than conventional dosage forms. (It may depend on the strains they use.) Some probiotics can be found in yoghourt which is definitely not gastro-resistant. </p>\n\n<p>Regulatory requirements are much stricter for medicines than for supplements in most countries, so if one is concerned with the sufficient drug delivery and the accuracy of medical claims, it is useful to know that for medicines to be approved for marketing much firmer evidence about these (and other concerns) has to be submitted.</p>\n\n<hr>\n\n<p>Why does powder exist as a dosage form? There may be several reasons to produce and market oral powder as a dosage form: some people have difficulties to swallow capsules, it may depend on manufacturer's production line, powders allow for <strong>individualised</strong> dosage (measuring the dose for a specific patient - but I don't think this would be necessary with probiotics), hygroscopic excipients which are incompatible with capsule shell etc. </p>\n\n<p>The dose you take in powder <strong>is not more precise</strong> - even if it is sold in divided doses (each dose in one bag), because a small amount of powder can always remain on the walls. The precision of measurement is the same at best, if not in favour of the capsules.</p>\n\n<h2>How to chose?</h2>\n\n<p>Here are some of the questions that should be taken into account:</p>\n\n<ol>\n<li>Is the patient allergic/intolerant to any of the formulation's ingredients?</li>\n<li>Is there a form preferred by the patient's physician, for some medical reason?</li>\n<li>Which form is the most convenient one for you?</li>\n<li>Which form is accessible and affordable to you?</li>\n</ol>\n", "score": 7 }, { "answer_id": 1139, "body": "<p>If they both contain the exact same substance, then powder form may be easier to measure more precisely. However, I cannot find any studies indicating any significant difference between capsule and powder form. </p>\n\n<p>Additionally, I would like to give you <a href=\"http://sciencelife.uchospitals.edu/2014/11/25/do-probiotics-work/\" rel=\"nofollow\">this link</a> containing an interview with Dr. Stefano Guandalini, MD, Section Chief of Pediatric Gastroenterology, Hepatology, and Nutrition and Medical Director of the Celiac Disease Center at the University of Chicago.</p>\n\n<p>He gives a short list of probiotics which \"have been validated through clinical trials and published in peer-reviewed journals to show efficacy\". For the rest, he states, </p>\n\n<blockquote>\n <p>\"Outside of this incredibly short list, however, there is nothing\n else. There is no other probiotic that has been found to be effective\n in rigorous, controlled clinical trials. This is not to say they\n aren’t working, it’s just to say we don’t have any scientific proof\n yet.\" </p>\n</blockquote>\n", "score": 3 }, { "answer_id": 11321, "body": "<p>I was told by a gastroenterologist at the IWK children's hospital in Halifax NS ( regarding medications my child had to take - that many things are excreted from our body when taken in capsul form before it gets a chance to work. An example the doctor gave me is when people take Metamucil capsules they do not get the effect bc the capsul goes through the system often before it is effective. The doctor recommended for someone taking Metamucil to take the powder form rather than the capsul. I would think the same idea would affect probiotic capsules. I started opening my capsule and putting the powder on my oatmeal / food and taking it that way. </p>\n", "score": 0 } ]
1,133
CC BY-SA 3.0
Probiotic: capsule or powder?
[ "stomach", "pill", "probiotics" ]
<p>What form of probiotic has the greatest health benefit- Capsule or powder?</p> <p>I have searched for it but the results talk about everything on probiotics except my question! <br/><a href="https://i.stack.imgur.com/sm6oH.png" rel="noreferrer">(A snapshot of my endeavors)</a></p> <p>In my opinion it is better to use capsule since it will protect the bacteria from the acid environment in the stomach. But then I'm skeptical about that: if the powder form is useless, why does it exist?</p>
8
https://medicalsciences.stackexchange.com/questions/1157/does-some-food-increase-pollen-allergy-symptoms
[ { "answer_id": 1161, "body": "<p>There are foods that won't increase your pollen allergy symptoms, but instead cause them. This is a condition called Oral Allergy Syndrome, also known as Pollen-Food Allergy Syndrome.<sup><a href=\"http://en.wikipedia.org/wiki/Oral_allergy_syndrome\" rel=\"nofollow\">1</a></sup> This is caused by a reaction to foods that contain similar ingredients or proteins to the type of pollen they are allergic to. So while this allergy is a bit different than just a regular pollen allergy, it is likely that, if you have a pollen allergy, there will be foods that trigger the same symptoms you may get from your pollen allergies.<sup><a href=\"https://www.rush.edu/health-wellness/discover-health/pollen-food-allergy-syndrome\" rel=\"nofollow\">2</a></sup></p>\n\n<p>There are a few common types of pollen allergies that have foods associated with them. Ragweed allergy, which is caused by the pollen of ragweed and mainly causes symptoms like sneezing, itchy throat, stuffy/runny nose, and possible trouble breathing. Some of the foods that may cause these symptoms include watermelons, cantaloupes, bananas, and honey.<sup><a href=\"http://acaai.org/allergies/types/ragweed-allergy\" rel=\"nofollow\">3</a></sup></p>\n\n<p>A birch pollen allergy is also a common allergy which has many symptoms similar to those of ragweed allergy. Foods which many trigger those symptoms are kiwi, pears, apples, plums, cherries, carrots, and almonds. Grass pollen allergy is the other common type of pollen allergy and its symptoms, which are also like ragweed and birch allergy symptoms, can be triggered by foods like tomatoes, celery, peaches, and oranges. To help avoid the above mentioned foods, you can try many things, such as cooking the food or peeling it, if it is possible.<sup><a href=\"http://www.webmd.com/allergies/features/oral-allergy-syndrome-foods\" rel=\"nofollow\">4</a></sup></p>\n\n<hr>\n\n<p><sup><a href=\"http://en.wikipedia.org/wiki/Oral_allergy_syndrome\" rel=\"nofollow\">1: Oral Allergy Syndrome</a></sup></p>\n\n<p><sup><a href=\"https://www.rush.edu/health-wellness/discover-health/pollen-food-allergy-syndrome\" rel=\"nofollow\">2: Recognizing pollen food allergy syndrome</a></sup></p>\n\n<p><sup><a href=\"http://acaai.org/allergies/types/ragweed-allergy\" rel=\"nofollow\">3: Rag Weed Allergy</a></sup></p>\n\n<p><sup><a href=\"http://www.webmd.com/allergies/features/oral-allergy-syndrome-foods\" rel=\"nofollow\">4: Foods That May Worsen Pollen Allergies</a></sup></p>\n", "score": 4 } ]
1,157
CC BY-SA 3.0
Does some food increase pollen allergy symptoms?
[ "allergy", "food-safety", "pollen" ]
<p>As a pollen allergic, should I avoid of eating some kinds of food which may increase pollen allergy symptoms?</p>
8
https://medicalsciences.stackexchange.com/questions/1213/is-it-safe-to-drink-urine-when-you-have-nothing-else-to-drink
[ { "answer_id": 1215, "body": "<p>If you are in a no-other-liquid situation then not, it's not safe to drink. The problem is that your urine is a way to remove superfluous minerals and other stuff from the body. The body's job, especially in a state of dehydration, is to remove this waste with the least amount of water sufficient to flush it away. </p>\n\n<p>If you then drink this urine, you are ingesting back all the salts you just got rid of. You are not getting your liquid-to-salts ratio better, you are making it worse. So when you are already dehydrated, you get dehydrated even quicker if you drink your urine. </p>\n\n<p>If you are at no risk of dehydration (you can additionally ingest sufficient water from drinks or food), then the above does not apply. As long as you don't have an urinary tract infection, your urine is also sterile, so you are not at risk of infection either. This makes urine safe to drink. </p>\n\n<p>There are people who drink urine (outside of dehydration situations) for supposed health benefits, but I have never heard of any evidence that such benefits exist. </p>\n\n<p>I don't know of peer reviewed sources for this, but the dangers of drinking urine for survival are both logical from a theoretical view point and common knowledge in outdoor lore, for example see <a href=\"http://survivalcache.com/water-purification/\" rel=\"nofollow noreferrer\">http://survivalcache.com/water-purification/</a>. </p>\n\n<p>The <a href=\"https://outdoors.stackexchange.com/questions/264/is-drinking-urine-safe\">Outdoors</a> site has the same question, with a suggestion for a possible purification method which might remove the dissolved minerals. But urine is also rich in organic compounds and starts breeding bacteria almost immediately upon leaving your body. So I'd be weary to try it: fresh urine is safe, but urine which has stood around at room temperature isn't. </p>\n", "score": 8 } ]
1,213
CC BY-SA 3.0
Is it safe to drink urine when you have nothing else to drink?
[ "nutrition", "water", "emergency", "urine", "drinks" ]
<p>What if there was a situation where someone had no water to drink or food to eat. Would it be safe for them to drink their own urine? What are the possible risks of doing this? Could there be any benefits?</p>
8
https://medicalsciences.stackexchange.com/questions/1270/can-waterproof-swim-cap-be-good-for-people-with-ear-infections
[ { "answer_id": 1271, "body": "<p>It sounds like you're talking about otitis externa, an infection of the ear canal, a condition where you really should avoid getting any water in your ear.</p>\n\n<p>You've already identified that the cap in question is not really waterproof. </p>\n\n<p>The best way (and really the only way) to keep water out of your ear is to stay out of the water until your ear has had time to clear the infection.</p>\n\n<p>To bathe, you can make a cheap waterproof ear plug by working a generous amount of petroleum jelly into a cotton ball, and using that as an earplug. You can also buy a special soft wax at most pharmacies. People roll a ball of the soft wax in their hands and press it into the outer ear. </p>\n\n<p>Once the infection is healed, if you're not prone to such infections, you can use home-made or pharmacy bought ear drops after occasional swimming which will help maintain the proper environment to minimize infection in the ear. Use of a hair dryer on low to dry your ear is also useful.</p>\n\n<p>High-grade silicone ear plugs can be used once the ear is healed, <em>however</em>, <em>ear plugs can aggravate or cause the condition</em>, so swimmers (or people occupationally required or recommended to wear ear plugs) usually consult with ear specialists to work out the best plug to use which will not cause damage to the ear canal, something critical for prevention.</p>\n\n<p><sub><a href=\"http://www.aafp.org/afp/2001/0301/p927.html\">Otitis Externa: A Practical Guide to Treatment and Prevention</a></sub></p>\n", "score": 6 } ]
1,270
CC BY-SA 3.0
Can &quot;Waterproof Swim Cap&quot; be good for people with ear infections?
[ "infection", "otolaryngology", "ear", "swimming" ]
<p>OK, I have an ear infection. The doctor says that I should not allow any water to go into my ears. However, I want to swim, but I don't want any water (even a tiny drop of water) go into my ears.</p> <p>So, what should I do?</p> <p>I heard there is a "Waterproof Swim Cap" for swimmers? See samples at <a href="http://www.swimcapsguide.com/best-waterproof-swim-cap/" rel="nofollow">this site about swimcaps</a>.</p> <p>But I'm not sure whether it will prevent any tiny drops of water from going into my ears. I doubt that.</p>
8
https://medicalsciences.stackexchange.com/questions/1297/why-omega-3-6-ratio-is-important
[ { "answer_id": 10388, "body": "<p>The book Living a Century or More by William Cortvriendt MD, which has a lot of scientific sources that I don't have the expertise to judge but seem reliable, says in the subchapter \"Omega-3 PUFAs and inflammation\" that</p>\n\n<blockquote>\n <p>...COX can in fact stimulate or inhibit inflammation. When omega-3 PUFAs come into contact with COX, they will inhibit inflammation. However when COX comes into contact with omega-6 PUFAs then inflammation will be stimulated.</p>\n</blockquote>\n\n<p>Note that inflammation is often an appropriate response by the body, but too much of it is harmful. This explains why the ratio is important: you don't want too little or too much. There may be other effects.</p>\n\n<p>The ideal ratio is between 5:1 and 1:1 in favour of omega-6. The typical ratio is much higher in favour of omega-6. That's why food and supplements with omega-3 are popular.</p>\n\n<p><strong>EDIT</strong>: you're trying to have low body fat. Of course the ratio can be controlled in two ways: increase omega-3 or decrease omega-6. If you want to keep total fat low, you could consider limiting omega-6. But keep in mind that these are healthy, unsaturated fats. If that's an option, you should definitely cut trans fats instead, and maybe saturated fats.</p>\n", "score": 3 }, { "answer_id": 1312, "body": "<p><a href=\"https://www.google.ca/url?sa=t&amp;rct=j&amp;q=&amp;esrc=s&amp;source=web&amp;cd=2&amp;ved=0CB8QFjAB&amp;url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpubmed%2F12442909&amp;ei=3R6FVdGmEYKuoQTDuYToCw&amp;usg=AFQjCNH8dDURblsTT3fkyTWv3Q0AsGVhaQ&amp;sig2=T9AqdFHg_Wj5XQv3fCj_OA&amp;bvm=bv.96339352,d.cGU\" rel=\"nofollow\">From the NIH</a>:</p>\n\n<blockquote>\n <p>Several sources of information suggest that human beings evolved on a diet with a ratio of omega-6 to omega-3 essential fatty acids (EFA) of approximately 1 whereas in Western diets the ratio is 15/1-16.7/1</p>\n</blockquote>\n\n<p>This is not undisputed though.</p>\n\n<p><a href=\"https://en.wikipedia.org/wiki/Omega-3_fatty_acid#Interconversion\" rel=\"nofollow\">https://en.wikipedia.org/wiki/Omega-3_fatty_acid#Interconversion</a> explains the importance. It's hard to summarize.</p>\n", "score": 2 } ]
1,297
CC BY-SA 3.0
Why omega-3/6 ratio is important?
[ "nutrition", "diet", "body-fat", "essential-oil" ]
<p>I'm 27 years old model and being under 8% body fat matters for me. I heard consumption of the right omega-3/6 ratio is important for this. I'm wondering whats the ideal ratio for my goal and why it is so important? </p>
8
https://medicalsciences.stackexchange.com/questions/1299/is-there-a-relationship-between-vitamin-d-levels-and-cholesterol
[ { "answer_id": 9480, "body": "<p>According to a couple of systematic reviews of studies, there is <strong>insufficient evidence</strong> about the lowering effect of vitamin D on blood cholesterol levels.</p>\n\n<ol>\n<li>Vitamin D, Evidence <a href=\"http://www.mayoclinic.org/drugs-supplements/vitamin-d/evidence/hrb-20060400\" rel=\"noreferrer\">Mayo Clinic (data from Natural Standard Research Collaboration)</a></li>\n</ol>\n\n<blockquote>\n <p>Many studies have looked at the effects of vitamin D alone or in\n combination with other agents for high cholesterol, but <strong>results are\n inconsistent.</strong> Some negative effects have been reported.</p>\n</blockquote>\n\n<ol start=\"2\">\n<li>Zitterman A et al, 2011, The role of vitamin D in dyslipidemia and cardiovascular disease [a systematic review] (<a href=\"https://www.ncbi.nlm.nih.gov/pubmed/21418036\" rel=\"noreferrer\">PubMed</a>)</li>\n</ol>\n\n<blockquote>\n <p>The vast majority of intervention studies <strong>did not show an effect</strong> of\n vitamin D on serum cholesterol levels.</p>\n</blockquote>\n", "score": 6 } ]
1,299
CC BY-SA 4.0
Is there a relationship between vitamin D levels and cholesterol?
[ "micronutrients", "cholesterol", "vitamin-d", "hdl", "ldl" ]
<p>I've been trying to read up on high cholesterol and there is <em>a lot</em> of information out there about it. In addition to &quot;don't eat fatty foods&quot; and &quot;exercise more,&quot; there are some sources that mention vitamin D as a possible contributor to improving cholesterol levels.</p> <blockquote> <p>The test group received a daily dose of 1,000 mg of elemental calcium along with 400 IUs of vitamin D3....</p> <p>Blood levels of vitamin D, fasting plasma triglycerides, HDL, and LDL cholesterol levels were assessed at the beginning and end of the trial. After two years, women who received the vitamin D and calcium supplements had a 38 percent increased mean vitamin D level compared to the placebo group.</p> <p>They also had a 4.46-mg/dL mean decrease in LDL. Furthermore, higher vitamin D concentrations were associated with higher HDL combined with lower LDL and triglyceride levels.</p> </blockquote> <h2>Edit:</h2> <p>The quote was originally from <a href="http://articles.mercola.com/sites/articles/archive/2014/04/14/vitamin-d-cholesterol-levels.aspx" rel="nofollow noreferrer">Mercola</a>, but, the article seems no longer to exist. However, the originating study seems to be Schnatz, et al. (<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5234488/" rel="nofollow noreferrer">2014</a>)</p> <p>It looks like there is a correlation, but I'm curious how that works.</p> <h2>References</h2> <p>Schnatz, P. F., Jiang, X., Vila-Wright, S., Aragaki, A. K., Nudy, M., O'Sullivan, D. M., Jackson, R., LeBlanc, E., Robinson, J. G., Shikany, J. M., Womack, C. R., Martin, L. W., Neuhouser, M. L., Vitolins, M. Z., Song, Y., Kritchevsky, S., &amp; Manson, J. E. (2014). Calcium/vitamin D supplementation, serum 25-hydroxyvitamin D concentrations, and cholesterol profiles in the Women's Health Initiative calcium/vitamin D randomized trial. <em>Menopause, 21</em>(8), 823–833. <a href="https://doi.org/10.1097/GME.0000000000000188" rel="nofollow noreferrer">https://doi.org/10.1097/GME.0000000000000188</a></p>
8
https://medicalsciences.stackexchange.com/questions/1341/what-is-the-mechanism-of-heartburn
[ { "answer_id": 3889, "body": "<p>WebMD has <a href=\"http://www.webmd.com/heartburn-gerd/guide/understanding-heartburn-basics\" rel=\"nofollow\">an interesting article on heartburn</a> that states<sup>1</sup></p>\n\n<blockquote>\n <p>With gravity's help, a muscular valve called the lower esophageal sphincter, or LES, keeps stomach acid in the stomach. The LES is located where the esophagus meets the stomach -- below the rib cage and slightly left of center. Normally it opens to allow food into the stomach or to permit belching, then closes again. But if the LES opens too often or does not close tight enough, stomach acid can reflux, or seep, into the esophagus and cause the burning sensation.</p>\n</blockquote>\n\n<p>This would seem to be something of a union of both theories of heartburn. I was slightly doubtful - the article doesn't cite a particular source - but I was able to do a bit of digging on my own and found a few papers and other reliable sources that support this.</p>\n\n<ul>\n<li><p><a href=\"http://www.ncbi.nlm.nih.gov/pubmed/15836451\" rel=\"nofollow\">Boeckxstaens (2005)</a> states (abstract only)</p>\n\n<blockquote>\n <p>The two typical examples of dysfunction of the LOS are achalasia and gastro-oesophageal reflux disease (GORD). . . . GORD results from failure of the antireflux barrier, with increased exposure of the oesophagus to gastric acid. This leads to symptoms such as heartburn and regurgitation, and in more severe cases to oesophagitis, Barrett's oesophagus and even carcinoma.</p>\n</blockquote></li>\n<li><p><a href=\"http://www.surgery.usc.edu/thoracic/esophagealmotilitydisorders.html\" rel=\"nofollow\">The Keck School of Medicine</a> states</p>\n\n<blockquote>\n <p>The esophagus is a muscular tube that connects the pharynx in the throat to the stomach. There are two sphincters at each end, an upper esophageal sphincter and a lower esophageal sphincter. With normal swallowing there is an incredible coordination of neurologic and muscular events for the food or liquid to efficiently pass from the mouth and into the stomach. Any dysfunction in this process can manifest as difficulty swallowing solids and liquids, regurgitation of undigested food, chest pain, and even heartburn.</p>\n</blockquote></li>\n<li><a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1382806/\" rel=\"nofollow\">Spechler et a. (1995)</a> writes\n\n<blockquote>\n <p>Heartburn, the main symptom of gastrooesophageal reflux disease (GORD), might be expected to occur infrequently in achalasia, a disorder characterised by a hypertensive lower oesophageal sphincter (LOS) that fails to relax.</p>\n</blockquote></li>\n</ul>\n\n<p>It appears the dysfunction of the LES/LOS is considered to be a cause of heartburn, specifically causing GORD, which then leads to heartburn.</p>\n\n<p>I'd like to emphasize that heartburn generally isn't a standalone illness, but a symptom of something else, just like a sore throat may be a symptom of, say, strep throat. This isn't always the case, but it generally is the case for instances of persistent heartburn.</p>\n\n<hr>\n\n<p><sup>1</sup> The Mayo Clinic also has <a href=\"http://www.mayoclinic.org/diseases-conditions/heartburn/basics/causes/con-20019545\" rel=\"nofollow\">a rather accessible article</a> for anyone who doesn't want to trudge through scientific papers.</p>\n", "score": 5 } ]
1,341
CC BY-SA 3.0
What is the mechanism of heartburn?
[ "digestion" ]
<p>My father recently forwarded me a factoid saying:</p> <blockquote> <p>most of us believe that heartburn is caused by excess production of gastric acid. In fact, in most cases it is caused by improper functioning of the stomach muscles, which increases the pressure within the stomach. This is why antacids create a very short-lived relieve, while taking herbs which soothe the stomach muscles are a permanent solution to the problem. </p> </blockquote> <p>To me, this sounds like bad advertising copy. But before I dismiss it completely, could they be partially or even completely right? What causes heartburn, is it acid overproduction, musculature problems, or something else?</p>
8
https://medicalsciences.stackexchange.com/questions/1469/what-is-junk-food-when-doctors-advise-to-avoid-junk-food-what-does-that-mean
[ { "answer_id": 1472, "body": "<p>Junk food is a somewhat generic term that basically includes calories from food that has no real nutritional value, or is so loaded with artificial flavors, added sugars/fats that it overwhelms the nutritional value that was there.</p>\n\n<p>Many of the items on your list <em>could</em> be considered junk food, depending on how they are eaten, how much and how often.</p>\n\n<p>For example, a Domino's thick crust pizza with pepperoni, sausage, extra cheese is loaded with saturated fats, lots of calories for not a lot of substance. However, you could get a thin crust pizza with a light amount of cheese, green peppers, mushrooms and black olives, and while still not the best of foods would be a much better option.</p>\n\n<p>Same for fruit juice - If you get a pure juice such as a squeezed orange juice with no additives, it will be much better than a cranberry juice from extract with added sugar.</p>\n\n<p>Also, as noted in this <a href=\"http://www.webmd.com/diet/junk-food-facts\">WebMD article on junk food</a>, these foods tend to be less satiating, that is they satisfy hunger much less than \"real\" foods, so that you typically end up eating more of them to satisfy hunger, which in turn leads to higher caloric intake.</p>\n\n<p>Other items, such as the chocolate, spring roll may not be the best (Depending on what is in the spring roll), but in little bits are ok. It's very hard to eat a clean diet, especially if you are busy, but with some planning and cooking ahead, you can make a diet very healthy, and still leave room for some items like chocolates, candies. </p>\n\n<p>As long as the junk food is limited in intake, and doesn't make up the majority of the diet (As a personal rule, I try to limit \"junk\" calories to no more than 10% of my weekly intake), a little bit should be fine.</p>\n\n<p>However, in light of this being a doctor's recommendation, and given the lab values in your other question, it might be a good idea to have a consultation with a dietitian/nutritionist to help create an achievable, healthy eating plan.</p>\n", "score": 9 } ]
1,469
CC BY-SA 3.0
What is Junk food? When doctors advise to avoid junk food, what does that mean?
[ "food-safety" ]
<p>A doctor has advised my friend to leave off eating junk food. </p> <p>Following are things which he eats generally, but which are junk among them?</p> <ol> <li>Pizza(Dominos)</li> <li>Fruit Juice</li> <li>Pastry (Chocolate)</li> <li>Soyabean (Roasted or Roasted Creamy nut butter)</li> <li>Milk</li> <li>Soya Cheese</li> <li>Indian Puchkas (having Mint water, asofoetida water, gauva water)</li> <li>Spring Roll (Fried in Olive oil)</li> <li>Veg Momos</li> <li>Burger </li> </ol>
8
https://medicalsciences.stackexchange.com/questions/1474/does-sitting-idle-for-one-month-without-work-lead-to-depression
[ { "answer_id": 1545, "body": "<p>I've suffered from depression quite a few years in my life. One basic long-term cause I have found is my basic worldview - whether I see reality as fundamentally \"good\" or \"bad\". This takes a long time to improve.</p>\n\n<p>But in the short term, I find my feelings strongly influenced by my ability to effectively respond to what life has brought along. If I set twenty goals and fail at all in a row, I tend to feel pretty low, whereas if I succeed then I tend to feel alright. When I advise students beginning research in chemistry, for example, I suggest that if they start to get frustrated to go \"wash the dishes\". This is helpful because washing the glassware is an activity where success is very likely, whereas chemical research can be fraught with disappointments easily beyond the ability of a novice (or even expert) chemistry student to predict.</p>\n\n<p>What we are seeing here is a phenomenon called <a href=\"https://en.wikipedia.org/wiki/Learned_helplessness\" rel=\"nofollow\">learned helplessness</a>. Since it affects rodents it should come as no surprise that it affects us too. All it amounts to is a basic learning process that generalizes recent failure at a particular task to be a reduced ability to accomplish all tasks. Unlike rodents, though, we have the advantage of seeing through reason that the depressed feelings are unjustified, and acting out of reason in spite of how we feel. Students with difficult or impossible chemistry research assignments can still know themselves as competent chemists and worthwhile people.</p>\n\n<p>It could also be burn out. How long have you been at the same computer-related occupation? I've been an application developer for the last ten years myself, but my life is full of other activities outside of work. Your desire to be outside may be your healthy need for a variety of activities. This would be a good time to go camping. It sounds like you are ready for a career change too, but you will need peace of mind and vision to lead you to the next one. That's my main advice - do what it takes to relax so you can reflect and know what to do.</p>\n", "score": 5 } ]
1,474
CC BY-SA 3.0
Does sitting idle for one month without work lead to depression?
[ "depression" ]
<p>I do 8 hours of work sitting before a computer. </p> <p>Because of no work or only performing a few actively-mobile jobs; I was sitting idle for last one month. I've gotten new work since then, but I do not want to do it for the below-listed reasons.</p> <p>Symptoms I'm experiencing include:</p> <p>My mind remains clouded, full of white noise, and I always feel like going outside. Even after I return, I immediately want to leave. The muffled sensation in my ears is not helped by cleaning.</p> <p>After months of no work, I feel torpid and completely lack motivation; I am forgetful about what little I do feel motivated to involve myself in. My self-esteem has taken a steep downturn, as well.</p> <p>Could anyone please explain whether any of this are symptoms of insanity or just depression?</p>
8
https://medicalsciences.stackexchange.com/questions/1480/how-to-tell-if-the-common-cold-has-turned-to-an-infection
[ { "answer_id": 12954, "body": "<p>As has been pointed out in the comments, a common cold is already a (viral) infection. By far the largest part of upper airway infections are viral and the body is very capable of clearing them up.</p>\n\n<p>It is a common misconception that that the colour of the mucus gives information about whether it is viral or bacterial. <a href=\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3410464/\" rel=\"nofollow noreferrer\">This study</a> shows that the sensitivity of yellowish or greenish sputum used as a test for a bacterial infection was 0.79 (95% CI 0.63–0.94); the specificity was 0.46 (95% CI 0.038–0.53), which is very low.</p>\n\n<p>A visit to your doctor for a cold is almost never necessary. Even in the case that there is a bacterial infection, your body can almost always get rid of it itself. <a href=\"https://www.ncbi.nlm.nih.gov/pubmed/23076918\" rel=\"nofollow noreferrer\">This Cochrane review</a> concludes that in acute, uncomplicated rhinosinusitis (which is, essentially, what we call \"a cold\") there is no place for antibiotics. It may cause the cold to be over faster than it would be without antibiotics, but without the antibiotics there is a very very low rate of complications. Antibiotics cause adverse events and resistance of bacteria, so they should not be used without reason. <br>\nAs there is no reason for antibiotics, a visit to your doctor will also not be useful.</p>\n\n<p>A subsequent upper airway infection with coughing is often caused by something called post-nasal drip (essentially mucus from the nose dripping into the throat), which sucks but doesn't warrent a visit to the doctor. Signs of a possible pneumonia are: fever for >3 days or recurrent fever after a few fever-free days, dyspnea or wheezing (this is based on the <a href=\"https://www.nhg.org/standaarden/samenvatting/acuut-hoesten#idp35451712\" rel=\"nofollow noreferrer\">Dutch guidelines</a> so I don't have an English source for this). In this case, I would definitely recommend going to your doctor. There is still a realistic chance that you're not going to need antibiotics, but that is a decision the doctor needs to make based on the specific circumstances and this cannot be assessed over the internet.</p>\n", "score": 3 } ]
1,480
CC BY-SA 3.0
How to tell if the common cold has turned to an infection
[ "infection", "common-cold", "bacteria", "virus" ]
<p>I am very susceptible to the common cold. I get it at least 2 - 3 times a year. Sometimes it goes away in a couple of days, sometimes it develops into a nasty throat/lung infection with an awful cough and I need to take inhalers. I have no asthma in general though. </p> <p>I have this theory that if the mucous that comes up in the cough and through the nose is yellow/green, then it is an infection and merits a doctor visit. if it is clear, then it is just a cold and I should wait it out.</p> <p>Is the idea wrong?</p>
8
https://medicalsciences.stackexchange.com/questions/1484/how-do-topical-steroid-withdrawal-relate-to-adrenal-insufficiency
[ { "answer_id": 1494, "body": "<p>Good question! The missing bit of information here is that topical steroids are usually not absorbed systemically at high enough levels to cause adrenal suppression. However, they sometimes are. I shall explain.</p>\n\n<p>First of all, regarding the relationship between <em>systemic</em> corticosteroid administration and adrenal insufficiency, please see <a href=\"https://health.stackexchange.com/a/1203/165\">this answer</a>. The basic idea (which I think you understand) is that exogenous administration of medications that mimic cortisol (a hormone produced in the adrenal gland) suppress the body’s processes for stimulating the hormone naturally. The adrenal gland atrophies due to the lack of natural stimulation. This causes a problem if the medication is suddenly withdrawn, because the body can’t quickly recover the ability to produce cortisol itself. This is called <strong>adrenal insufficiency</strong> or <strong>HPA axis suppression</strong>.<sup>1</sup> </p>\n\n<p>Now to your question:</p>\n\n<blockquote>\n <p>How do topical steroid withdrawal relate to adrenal insufficiency?</p>\n</blockquote>\n\n<p>The answer is that <em>if</em> topical steroids are absorbed into the bloodstream at high enough levels for a long enough time to suppress the HPA axis, they will cause adrenal insufficiency. Usually this degree of absorption occurs only with the use of “Group I” topical steroids, the strongest ones. <a href=\"http://www.the-dermatologist.com/files/docs/DrugGuide1006.pdf\" rel=\"nofollow noreferrer\">This list</a> shows the different categories of topical steroids by potency. The “super-potent” Group I includes:<sup>2</sup> </p>\n\n<ul>\n<li>Betamethasone 0.05% </li>\n<li>Clobetasol 0.05%</li>\n<li>Diflurasone 0.05%</li>\n<li>Halobetasol 0.05%</li>\n<li>Flucinonide 0.1%</li>\n</ul>\n\n<p>The most important factors that determine whether or not HPA suppression will occur are the potency of the drug, the dose, and the duration of use. The Group I agents can cause significant HPA suppression if used for two or more weeks at a dose of ~2g/day. Other factors that predispose to HPA suppression include:</p>\n\n<ul>\n<li>application to permeable areas (face, mucous membranes)</li>\n<li>occlusive dresssings</li>\n<li>compromised skin integrity</li>\n<li>young age</li>\n</ul>\n\n<p>The first list in your question appears to mostly outline <em>local</em> effects of withdrawing topical steroids. These are possible with less potent steroids and do not require systemic absorption. The second list, on the other hand, describes a syndrome of adrenal insufficiency. These are likely only the circumstances described above. </p>\n\n<hr>\n\n<p><strong>Notes</strong> </p>\n\n<ol>\n<li><p>HPA stands for hypothalamus &#8594; pituitary &#8594; adrenal, the pathway for producing cortisol.</p></li>\n<li><p>List was expanded a bit from that link using Bolognia et al., below.</p></li>\n</ol>\n\n<hr>\n\n<p><strong>References</strong> </p>\n\n<p>Tadicherla S, Ross K, Shenefelt PD, Fenske NA. <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/?term=2002793\" rel=\"nofollow noreferrer\"><em>Topical corticosteroids in dermatology</em></a>. J Drugs Dermatol. 2009;8(12):1093.</p>\n\n<p>Walsh P, Aeling JL, Huff L, Weston WL. <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/?term=8349876\" rel=\"nofollow noreferrer\"><em>Hypothalamus-pituitary-adrenal axis suppression by superpotent topical steroids.</em></a> Am Acad Dermatol. 1993;29(3):501.</p>\n\n<p>Bolognia JL, chaffer JV, Duncan KO, Ko CJ. <em>Dermatology Essentials.</em> Appendix 6: Potency ranking of some commonly used topical glucocorticosteroids. © 2014, Elsevier Inc.</p>\n\n<p>For further reading see:</p>\n\n<ol>\n<li><p>This powerpoint presentation from the FDA: <a href=\"http://www.fda.gov/ohrms/dockets/ac/03/slides/3999S1_03_Cook.ppt.\" rel=\"nofollow noreferrer\">The FDA Experience: Topical Corticosteroids and HPA Axis\nSuppression</a>.<br>\nThis elaborates on the special problems of the pediatric population and discusses the likelihood and extent of suppression with lower potency steroids. </p></li>\n<li><p>Gilbertson EO, Spellman MC, Piacquadio DJ, Mulford MI. <a href=\"http://www.ncbi.nlm.nih.gov/pubmed/9486706\" rel=\"nofollow noreferrer\"><em>Super potent topical corticosteroid use associated with adrenal suppression: clinical considerations.</em></a> Am Acad Dermatol. 1998 Feb;38(2 Pt 2):318-21.</p></li>\n</ol>\n", "score": 8 } ]
1,484
CC BY-SA 4.0
How do topical steroid withdrawal relate to adrenal insufficiency?
[ "topical-cream-gel", "steroids", "drug-withdrawal", "eczema" ]
<p>In the International Topical Steroid Awareness Network (ITSAN) website, there is a <a href="http://itsan.org/what-is-rss/#tab-f1c9d2cad5aa46946fb" rel="nofollow noreferrer">list of symptoms that relieve after you discontinuing topical steroid</a>. I will list here some of them:</p> <blockquote> <h3>Signs and symptoms of topical steroid withdrawal</h3> <ul> <li>Skin flushing bright red, resembling a sunburn</li> <li>Visible and measurable flaking of skin – appears to be ‘snowing’</li> <li>Oozing exudate</li> <li>Skin cycling between oozing, swelling, burning, and flaking</li> <li>Red sleeves: (arms/legs become red and inflamed, sparing palms/soles)</li> <li>Thermoregulation altered (feeling too cold or too hot)</li> <li>Hypersensitivity of the skin to water, movement, moisturizer, fabrics, temperature, etc.</li> <li>Nerve pain, sometimes described as “sparklers” or “zingers”</li> <li>Enlarged lymph nodes</li> <li>Fatigue</li> </ul> </blockquote> <p>I know that topical steroid drug is a subset of glucocorticoid drug, so I widen my search. Below is some signs and symptoms of <a href="https://en.wikipedia.org/wiki/Adrenal_insufficiency#Signs_and_symptoms" rel="nofollow noreferrer">adrenal insufficiency</a>:</p> <blockquote> <h3>Signs and symptoms of topical steroid withdrawal</h3> <p>Hypoglycemia, dehydration, weight loss, and disorientation. Additional signs and symptoms include weakness, tiredness, dizziness, low blood pressure that falls further when standing (orthostatic hypotension), cardiovascular collapse, muscle aches, nausea, vomiting, and diarrhea.</p> </blockquote> <p>Except some overlap (lethargy, insomnia, fatigue), I find no link from the topical steroid withdrawal and adrenal insufficiency. I have read wiki articles about <a href="https://en.wikipedia.org/wiki/Adrenal_crisis" rel="nofollow noreferrer">adrenal crisis</a>, <a href="https://en.wikipedia.org/wiki/Glucocorticoid#Withdrawal" rel="nofollow noreferrer">glucocorticoid withdralwal</a>, <a href="https://en.wikipedia.org/wiki/Topical_steroid" rel="nofollow noreferrer">topical steroid</a> and <a href="https://en.wikipedia.org/wiki/Addison%27s_disease" rel="nofollow noreferrer">Addison's disease</a>, but still can't find the link.</p> <p>How do topical steroid withdrawal relate to adrenal insufficiency?</p>
8
https://medicalsciences.stackexchange.com/questions/1488/increase-immunity-to-common-cold-and-cough
[ { "answer_id": 1500, "body": "<p>The \"common cold\" is a syndrome that is characterized by signs and symptoms of upper respiratory infection: sneezing, itchy or watery eyes, rhinorrhea, cough, and sinus congestion. Malaise (the feeling of \"feeling sick\") is reported, but is generally more mild than with the flu. Fever is uncommon with colds. Myalgias and arthralgias (muscle and joint aches) are also reported but are typically more mild than with flu).</p>\n\n<p>The common cold is invariably caused by viruses and more than one family of viruses is capable of producing this syndrome with varying degrees of severity and duration depending on the virus. The best known virus family is the <em>rhinoviridae</em>.</p>\n\n<p>Rhinovirus has at least 99 serotypes. This presents a challenge to the body's immune system as an immune response to one serotype may not provide any protection against other serotypes. It is possible for a person to be consecutively infected with rhinoviridae of different serotypes. The durability of immunity to a rhinovirus strain, once established, is not known. It remains possible that over time, a person can become susceptible to reinfection.</p>\n\n<p>Because human adaptive immunity requires antigen exposure, there is little that someone can do on their own to \"boost\" their specific immunity against cold viruses. There is no vaccine (so many viruses and serotypes to consider). Boosting non-specific immunity (the acute inflammatory mechanisms) is a strategy that has not been well explored, but this approach is hard to recommend. Non-specific immunity is a two-edged sword with the potential to damage the host's own body in addition to its role as the \"first responders\" to a pathogen.</p>\n\n<p><strong>Airborne like products.</strong> Over the counter products that purport to \"boost immunity to colds\" are largely clinically untested. Vitamin C has been examined. In a July 2007 study, researchers wanted to discover whether taking 200 milligrams or more of vitamin C daily could reduce the frequency, duration, or severity of a cold. After reviewing 60 years of clinical research, they found that when taken after a cold starts, vitamin C supplements do not make a cold shorter or less severe. When taken daily, vitamin C very slightly shorted cold duration.</p>\n\n<p>Most over the counter immune boosters for colds are vitamin B and C based, which makes them safe and reasonably non-toxic so their use can't be discouraged. Therapeutic doses of water-soluble vitamins usually result in very expensive urine.</p>\n\n<p><strong>Zinc.</strong> Recently an analysis of several studies showed that zinc lozenges or syrup reduced the length of a cold by one day, especially when taken within 24 hours of the first signs and symptoms of a cold. Studies also showed that taking zinc regularly might reduce the number of colds each year, the number of missed school days, and the amount of antibiotics required in otherwise healthy children. Zinc can potentially have some side-effects, so you should talk to your doctor before beginning zinc supplementation.</p>\n\n<p><strong>TLDR:</strong> Rhinoviridae is very infectious, lives outside the body for hours to days, and is readily transmitted by auto-inoculation from encounters with contaminated surfaces. The best \"immune booster\" for colds really, truly is frequent hand-washing.</p>\n", "score": 7 }, { "answer_id": 4910, "body": "<p><a href=\"http://www.nlm.nih.gov/medlineplus/ency/article/007165.htm\" rel=\"nofollow\">As explained here</a>, exercise is theorized to have a positive effect on the immune system via a few different mechanisms, although the rigorous proof that it does anything at all is still lacking (that's most likely a result of a lack of research in this area). As this source says, you should not overdo it, but then the amount of exercise that will be too much for you depends on your fitness level to begin with. So, the fitter you are the harder you can actually exercise before you pass the break even point where the negative effects start to grow larger than the positive effects. </p>\n", "score": 0 } ]
1,488
Increase immunity to common cold and cough
[ "prevention", "common-cold", "cough" ]
<p>What are some home remedies (preventive) that I can try on a regular basis to increase my immunity to common cold? I get it way too often, almost once every couple of months.</p> <p>Sometimes it is viral and goes away (although the cough lingers), other times, it turns into a chest-lung infection with a cough that wakes up the neighborhood.</p> <p>I don't smoke. I don't mind a bit of cold and runny nose, but the cough is really bothersome.</p>
8