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Vitamin D, part 1: back to basics
- conorh 6y agoThere was a lot of interest last time on this topic in a previous hacker news discussion [1] so posting this article by my wife (the parathyroid surgeon) here. If you have any questions feel free to post them here and she will check in. [1] https://news.ycombinator.com/item?id=24061164 https://news.ycombinator.com/item?id=24061164
- dilippkumar 6y agoGreat read! I'd love to read more posts in the future, but it's very unlikely that I'll come to devaboone.com every day to look for new posts. Can you please set up an RSS feed?
- conorh 6y agoWill do, she set it up on Wix herself to learn a little about how to do all of this. I'm surprised they don't offer an RSS feed, I'll help her out with that. edit: The feed is apparently https://www.devaboone.com/blog-feed.xml https://www.devaboone.com/blog-feed.xml and the Wix editor gives you no ability to add <head> tags, but there it is.
- roldie 6y agoThanks, subscribed!
- interfixus 6y agoThank you. Much appreciated, the feed and everything leading up to it, right back from the initial discussion.
- dilippkumar 6y agoThanks! Subscribed.
- jonny_eh 6y agoMaybe add a link to the site?
- bdickason 6y agoThanks for sharing. I skimmed the article looking for a specific set of info but may have missed it: how do bodies naturally/organically generate vitamin D and can that be sufficient or are supplements necessary? (E.g. I surf 5 days a week with sunscreen and go for walks regularly. Will I have enough vitamin D or should I supplement?)
- CarbyAu 6y agoStraight forward blood tests will tell you where you are at. Get a test, get your answer. I would hazard a guess that significant outdoor exposure would be enough, but I am not a doctor in any sense.
- neuronic 6y agoAlso, depending on your level of sun exposure and possible deficiency, you should probably supplement MUCH more than what has been usual for decades. You will find a max of 1000 IU and many supplements at daily doses way lower than that (300 - 700 IU). This is likely wrong: "Since all-disease mortality is reduced to 1.0 with serum vitamin D levels ≥100 nmol/L, we call public health authorities to consider designating as the RDA at least three-fourths of the levels proposed by the Endocrine Society Expert Committee as safe upper tolerable daily intake doses. This could lead to a recommendation of 1000 IU for children <1 year on enriched formula and 1500 IU for breastfed children older than 6 months, 3000 IU for children >1 year of age, and around 8000 IU for young adults and thereafter. Actions are urgently needed to protect the global population from vitamin D deficiency." [1] [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541280/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541280/
- Rotten194 6y agoI'm not a doctor, but my doctor told me when I asked that excess Vitamin D passes through your body harmlessly, so there's basically no reason not to supplement if you're worried you aren't getting enough.
- gojomo 6y ago
- ramraj07 6y agoThanks. What are your (or Devas) thoughts on the ritual vitamin company's products (http://ritual.com http://ritual.com)? They seem like the most researched multivitamin product I've seen but still never gotten an unbiased opinion!
- epmaybe 6y agoJust a thought - if your wife does indeed blog about recommended dosages, I'd suggest some sort of disclaimer included on the website to avoid liability. I'm not a lawyer, but sounds like a lot of headache if someone wanted to ruin your day.
- bravoetch 6y agoYou just man'splained that to someone that's an expert in their field.
- refurb 6y agoThe blog writer is an expert in legal liability when giving medical advice? That wasn’t manplaining at all.
- globular-toast 6y agoJust stop it.
- Dahoon 6y agoTo stoop to your level: only feminazi use those words. Please stop and say it in actual English.
- lawnchair_larry 6y agoLet’s never use that word again
- Angostura 6y agoDid you just assume the commenter's gender?
- epmaybe 6y agoI'm no vitamin D expert, but I am a physician, and my wife is a lawyer. I also didn't notice any disclaimer regarding medical advice on the currently linked blog post, so I thought I would at least mention it. Also, you assumed my gender which is rather interesting in and of itself.
- 6y ago
- charlieflowers 6y agoThis is excellent. An explanation from first principles about what Vitamin D does in our bodies that is accessible to lay people.
- kkaranth 6y agoGreat read! Are there more (preferably personal)blogs like this that make topics in medicine more accessible?
- astura 6y agohttps://sciencebasedmedicine.org https://sciencebasedmedicine.org
- baccheion 6y ago300-500 IU/kg/day vitamin D3. 5-10 mg vitamin K2 MK-4. 100 mcg vitamin K2 MK-7. 1.2 grams magnesium. 500-600 mg calcium from all sources. ZMA (if male). Eventually melatonin to keep at level of youth.
- reducesuffering 6y agoThat is ~30k IU Vitamin D3 a day, isn’t it? That’s an astonishingly outlier amount of D3 to be taking. The author strongly recommends against that much in a previous thread.[0] [0] https://news.ycombinator.com/item?id=24061164 https://news.ycombinator.com/item?id=24061164
- krick 6y agoYeah, that's like a really fucking lot. I was taking maybe half of that when I was extremely deficient, and about 3k currently (which I guess is still a bit more than I need, I just didn't take a blood test in a long time and assume I'm a tiny bit below the norm). And I weight way more than 60 kg you used for calculation.
- baccheion 6y agoIt's not a "blanket" (ie, time-tested) dose. On the other hand, Multiple Sclerosis patients take much much higher amounts without many issues. I've been taking at least 60,000 IU/day (no health issues) since the beginning of 2018, with some bouts of ~100,000 IU. The only issues from higher amounts of D3 stem from perturbation of calcium (increasing) and magnesium (decreasing) levels. Mainly addressed by swapping their RDAs.
- byproxy 6y agoWhere is this "prescription" coming from? I imagine you've done some diligence to get these numbers, just curious what convinced you.
- raxxorrax 6y agoI'll take the burger with fries, die perhaps some time earlier but lived a happy life instead. Seriously, even IF that cocktail would be healthy to someone, dosages would heavily vary between individuals.
- amgreg 6y agoThe author explains the following, regarding Vitamin D studies: > Most studies follow this pattern: Two sets of people are evaluated. One set has a certain disease (diabetes, for example). The other set does not have the disease. Vitamin D levels are measured in both groups. Vitamin D deficiency is found to be much more common in the group of diseased individuals. If this is true, I wonder if most studies aren’t falling short for failing to control for Vitamin D deficiency. Couldn’t the studies be structured differently? Let’s say we want to know the effects of Vitamin D on Covid. What if, instead of measuring Vitamin D deficiency in a group with the malady and a group without (analogous to what the author suggests most studies do): We had two groups made up of Vitamin D deficient people. We gave the first group a Vitamin D supplement and the other a placebo. We then observed both groups out in the wild (ideally a place with a high R), measuring for infections. If the supplement folks were infected at significantly lower rates than placebo folks, wouldn’t this be better at demonstrating causation?
- jonny_eh 6y ago> failing to control for Vitamin D deficiency Do you mean failing to control for the disease causing vitamin D deficiency? Because it seems that's the issue you're addressing with your proposed study design.
- pdr2020 6y agoI think the issue he's addressing with his design is whether supplementing vitamin D would actually CAUSE infection rates to fall - versus simply knowing that vitamin D levels and COVID infections are correlated.
- deleted 6y ago[deleted]
- choxi 6y agoTo your point, a confounding variable could be that diseased people go outside less (and therefore have less vitamin D)
- 6y ago
- nick_kline 6y agoThere's a lot more to this author that the average poster. Deva Boone was commenting in this thread [1], she's a doctor. Seems sensible and makes interesting points. She was posting under https://news.ycombinator.com/user?id=devaboone https://news.ycombinator.com/user?id=devaboone. Just posting this because there's always kind of wacky things said about the miracle of vitamin D and I was interested in what an actual doc has to say (as opposed to us programmers ;-)). 1. https://news.ycombinator.com/item?id=24061164 https://news.ycombinator.com/item?id=24061164 Vitamin D and covid-19 mortality.
- wyclif 6y agoInteresting that she never mentions the effects of sunlight on Vitamin D levels. I know she has talked about it in other threads on HN, but not in this article.
- petargyurov 6y agoThis was only part 1. I suppose in the next one she might. I hope she also covers recommended dosage and absorption.
- Havoc 6y agoMaybe she knows we’re all just sitting indoors in front of screens all day
- devaboone 6y agoHi, I'm the one who wrote the blog post. Thanks for commenting. Sunlight is important. There are a lot of things that are also important that aren't in the blog, simply because I couldn't cover all of them and keep the post to a manageable size. I like reading these comments to find out what people want to know, though, and what I should cover in the next post. Sunlight will be addressed.
- josephpmay 6y agoI recall reading a few years ago about an (Australian?) study That found that the non-bone health benefits correlated with Vitamin D were equally correlated with sun exposure. I’d be interested to know if any more research has been done on this.
- techer 6y agoThe Sunlight League https://en.m.wikipedia.org/wiki/The_Sunlight_League https://en.m.wikipedia.org/wiki/The_Sunlight_League 1924. Caleb Saleeby - admittedly complicates matters due to his eugenics background.
- simonebrunozzi 6y agoWhat an amazing article, written with such clarity and meaning (I have no idea how accurate it is, as I'm not a doctor or medical expert). I wish more people would write like this.
- devaboone 6y agoThanks! My goal is to write about medical topics in a way that anyone (especially non-medical people) can understand.
- electriclove 6y agoThis is great to read! I think there are 2 basic questions that many of us are looking for guidance on: How can I find out if I am deficient in Vitamin D? Can I do this without an office visit or lab visit? How much should I supplement with?
- smohare 6y agoYo might want to read https://sciencebasedmedicine.org/vitamin-d-supplements-do-not-reduce-the-risk-of-depression/ https://sciencebasedmedicine.org/vitamin-d-supplements-do-no... before you rush to buy supplements, at least.
- batter 6y agoIt's clear why she's interested in VitD as parathyroid surgeon. There are some thoughts that VitD deficiency is the root cause of hyperparathyroidism. I have another theory: it's sodium disbalance with calcium. That's why if you have bone ache some water with sodium will temporary relieve the pain. Even though it's not the root cause. It's simptom. At the same time keeping VitD active in your body requires Boron. Also boron is needed to keep your hormonal balance. And Boron impacts Zinc. And if Zinc is in proper place you won't get sick.
- sg47 6y agoQuestion for the author. I have historically had low Vitamin D levels and recently had my thyroid removed due to thyroid cancer. Do I need to be particularly worried or do anything to supplement my vitamin D?
- grenoire 6y agoBlood test!
- kwhitefoot 6y agoAs this site is predominantly read by people with software development experience I think Rob Pike's rules of programming are apposite here: https://news.ycombinator.com/item?id=24135189 https://news.ycombinator.com/item?id=24135189 Specifically rules 1 and 2: Rule 1. You can't tell where a program is going to spend its time. Bottlenecks occur in surprising places, so don't try to second guess and put in a speed hack until you've proven that's where the bottleneck is. Rule 2. Measure. Don't tune for speed until you've measured, and even then don't unless one part of the code overwhelms the rest.
- Gatsky 6y agoI was pretty excited about vitamin D for cancer prevention. I though it might explain higher cancer prevalence further away from the equator. But then Mendelian randomisation studies showed it made no difference. Having said that there was a large randomised trial (VITAL) with some trends towards reduced cancer burden. Only if BMI was normal however, which is highly salient of itself.
- manmal 6y agoVitamin D is a side effect of exposure to sunlight. Wouldn’t the more likely discerning factor be the irradiation with sunlight itself? There are thousands of papers on the positive effects of photobiomodulation (exposure to visible and near infrared photons): https://docs.google.com/spreadsheets/d/1ZKl5Me4XwPj4YgJCBes3VSCJjiVO4XI0tIR0rbMBj08/edit https://docs.google.com/spreadsheets/d/1ZKl5Me4XwPj4YgJCBes3...
- ilaksh 6y agoSince it seems some regular adequate exposure to sunlight is required for humans, my fantasy future-city building designs have a special type of glass that permits UV B.
- DoingIsLearning 6y agoDepending on the country you already have workplace regulations that mandate minimum natural light intensity levels at your workstation. It seems only logical that the next step is to regulate that HVAC can only apply selective UV filters on windows instead of UV wide spectrum filters. I am not sure what would be the manufacturing challenges for this? It would likely apply only for new construction but it would be a step forward.
- ilaksh 6y agoThere is glass like that but its only for special applications as far as I know and probably not a lot of quantity. So it might be basically the same thing they are doing but much larger scale.
- hrnnnnnn 6y agoYou need fancy lenses to do UV photography. From wikipedia: "For UV photography it is necessary to use specially developed lenses having elements made from fused quartz or quartz and fluorite." Veritasium has a video using a special UV setup, it's pretty cool - https://www.youtube.com/watch?v=V9K6gjR07Po https://www.youtube.com/watch?v=V9K6gjR07Po
- raxxorrax 6y agoGlass filters UVB, which is required for synthesis of vitamin D. It is nearly transparent for UVA that can also damage your skin (no sunburn, but cancer). So maybe wide spectrum filter would actually be preferable.
- lazyjones 6y ago> regular adequate exposure to sunlight is required for humans, How is this explained, by what mechanisms? Some of the effects we are observing might be the result of protection mechanisms for the skin.
- greenie_beans 6y agoI have literally no educational background about any of this, yet this was so well-written that I was able to understand most of it with hardly any cognitive work or re-reading. This only confirms my belief that informative writing should be written for the least knowledgeable person regardless of the assumed audience, and if anybody thinks you’re stupid for not understanding their informative writing, then that person is a jerk and should learn how to write better.
- devaboone 6y agoThank you! I wrote the blog post, and my goal was to make it so that someone without any medical background could understand it. By the time I finished, I wasn't sure if I had accomplished that. The article is still pretty dense with medical science. So glad you commented.
- tuna-piano 6y ago+1, I've heard so much about vitamin D in recent months (and even started taking supplementation myself)... this was super well written and informative. Can't wait for part 2 - please post to HN again!
- toomanybeersies 6y agoVitamin D deficiency is more or less inversely proportional to the amount of time one spends active and outside, isn't it? I'm sure this has been answered somewhere on the internet, but wouldn't it be reasonable to posit that a sedentary lifestyle is likely the root cause of many of these health issues correlated with vitamin D deficiency?
- WalterSear 6y agoYes, but not entirely. https://pubmed.ncbi.nlm.nih.gov/17218096/ https://pubmed.ncbi.nlm.nih.gov/17218096/ > In a study of Hawaiian surfers with sun exposure of at least 15 hours per week for the preceding 3 months, 25(OH)D levels ranged from 11 up to 71 ng/mL, demonstrating wide individual variation.
- lazyjones 6y ago15 hours per week isn't really much, is it?
- arethuza 6y agoI don't know - most weeks I spend perhaps that amount outdoors (say 8/9 hours hillwalking at the weekend and 6 hours during the week gardening) and that is far more than most people I know. However, that's in spring/summer/autumn and assuming the weather is OK. In December or January its entirely possible for me hardly to hardly see any sun at all due to short days (say 8am to 3pm) and poor weather - and if I am out I'll inevitably be covered in bad weather clothing. Edit: I started taking Vitamin D a few years back and saw a dramatic improvement in some areas. Edit2: Amusingly, I had no idea what Vitamin D was supposed to do when I started taking it, my wife had bought some and asked if I wanted some. It had a dramatic effect on anxiety levels that I was suffering from at the time - it was mid winter. The only side effect I noticed being truly bizarre and vivid dreams - again something that I didn't know about in advance but have read other people commenting on.
- 082349872349872 6y agoNot mentioned in the article: human skin depigmentation was an adaptive mutation to ensure adequate vitamin D production at higher latitudes. (The traditional diets of far northern people also supplement.) Compare lactose tolerance.
- autisticcurio 6y agoAre you sure? Melanin the skin pigment converts 99.9% of UV radiation into heat otherwise it damages deeper layers of the body. I'd say Melanin is there to protect us, so at polar latitudes, the need to protect from UV radiation drops off. Plus things like copper which is one of the chemicals used to make melanin is also used in other processes, for example some of the aromatic neurotransmitters. If you reduce chemicals to some neurotransmitters because its needed elsewhere in the body, what does it do to the brain? Look into hair pigmentation to get a better understanding. Remember diet restricts our intakes so some processes can appear to be rate limiting, when they are not, we are just a complex real-time chemical reaction. Feed any chemical reaction the right amount of chemicals for the environment and you can keep a chemical reaction going forever.
- neilwilson 6y agoCorrelation may not be causation, but it does provide a null hypothesis to fire at. And people with adequate vitamin D seem to die less (https://www.mayoclinicproceedings.org/article/S0025-6196(18)30183-6/fulltext https://www.mayoclinicproceedings.org/article/S0025-6196(18)...). Hence the conclusion in this paper (which does have dosages in it). https://www.mdpi.com/2072-6643/12/7/2097/htm https://www.mdpi.com/2072-6643/12/7/2097/htm "The bottom line is that there is no downside to increasing our intake of vitamin D to maintain serum 25(OH)D at at least 30 ng/mL (75 nmol/L), and preferably at 40–60 ng/mL (100–150 nmol/L) to achieve optimal overall health benefits of vitamin D."
- jjt-yn_t 6y agoI would think exercise in the sun would also play a role in that longevity.
- devaboone 6y agoThis is a good point. And I do want to get to more of the studies done in humans. Although I haven't discussed dosages yet, my advice on everything in life is pretty much: everything in moderation.
- hellofunk 6y agoI’m literally on the side of my chair waiting for part two. The first scientific article I’ve read that felt like a cliffhanger.
- kwhitefoot 6y agoInteresting article if you are interested in the background. But I want the conclusion first so that I can take action now not wait for some unspecified amount of time for part two. So I wish that authors of this sort of blog post, especially knowledgable and literate people like the author, would put a short summary of the information that ordinary people could actually use at the top of the page.
- kesor 6y agoWhy? It is already a problem that the "herd" is doing whatever some blog post tells them to. People need to understand, and to think for themselves. If someone does not understand the difference between causality and correlation - and just takes his dose of X mg of vitamin D then the whole post missed its point.
- redlizard 6y agoAre these studies just showing that vitamin D is a good predictor of income (because race is a good predictor of income)? Now that the US is starting to have conversations about racial inequality, every time I see a hackernews or reddit post on vitamin D I am asking myself that question. I have read several studies that link low income to higher mortality rates across several different diseases. [0] And several other studies that link education levels (which are inherently linked to childhood wealth levels) to worse mortality rates as well.[1] There is a link between lower vitamin d levels and skin color, with an obvious plausible explanation ( Melanin lowers skins ability to produce vitamin D).[2] In the U.S. at least there is a strong link between income, education levels, and skin color. [3] While I am hopeful that ongoing research will help us understand the mechanisms by which vitamin-D operates, I really worry that it is somehow a very well dressed red-herring. One one hand a promised panacea: vitamin d supplements, the other a complex economic and political problem that barely anyone can comprehend or are even willing to engage with. One of the more damning studies shows that vitamin d supplementation is good enough to remove your deficiency, it has reproduced really poorly on any of the other correlated health effects.[4] Are there any studies that someone can link that would alleviate my concerns? When these kind of population health studies are conducted (I am in no way familiar with how they are actually done), how are factors like income inequality and education level generally controlled for? And an interesting article that may or may not be valid that kind of got me on the road of becoming a vitamin D skeptic: https://www.outsideonline.com/2380751/sunscreen-sun-exposure-skin-cancer-science https://www.outsideonline.com/2380751/sunscreen-sun-exposure... [0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866586/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866586/ [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4435622/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4435622/ [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5946242/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5946242/ [3] https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0190640#sec014 https://journals.plos.org/plosone/article?id=10.1371/journal... [4] https://www.nejm.org/doi/full/10.1056/NEJMoa1809944 https://www.nejm.org/doi/full/10.1056/NEJMoa1809944
- Santosh83 6y agoGreat article but am unable to figure out on which site one has to create an account to be able to login to comment on the article. A pop-up box prompts me to login, but doesn't specify where to register if I'm not already having an ID...
- Abishek_Muthian 6y agoI've had Vitamin D deficiency from the child and I suffer from Achondroplasia(not diagnosed until recently). I've had ilizarov fixations twice during childhood to fix the bow legs and I had explicit medication for Vitamin -D only when I was teen for couple of years. But after 15 years, I nearly ended-up becoming a Quadriplegic[1] and I was told my bone condition was like that of 80 year old (I was 32). For the past 2 years I've had single Zoledronic acid injection each year to treat the osteoporosis along with monthly Vitamin D3-Cholecalciferol 60K IU, recent tests showed that there has been about ~ 10% improvement in bone density at some areas and few areas have become worse. I often wonder if whether I had been put through proper Vitamin D supplement from childhood, the situation would have turned out this bad. Anyways, Vitamin D seems like the new Yoga and everything from memory to COVID prevention is being attributed to it; but I can say one thing for sure from my experience - If your Vitamin D is low, take proper medication on doctor's advice and follow it up regularly as bone diseases don't come with warning unlike other organs in our body. [1]https://abishekmuthian.com/i-was-told-i-would-become-quadriplegic-68c0371e6f05/ https://abishekmuthian.com/i-was-told-i-would-become-quadrip...
- jokowueu 6y agoIf I may add please look into harmala alkaloids specifically harmine to aid in bone density . It is completely unregulated in the USA and the doses required to achieve a proper response isn't high enough to cause nausea or other effects . Dosing twice a day is good enough . But as always do you own research and read up on contradictions . I recall reading this many years ago because if its effects on DYRK1A
- Abishek_Muthian 6y agoAlthough I'm not currently planning to try any self-medication, I will study about Harmala alkaloids to learn about its significance with bone density. Thank you.
- jokowueu 6y ago"bone anabolics" is a great term to research these substances
- radu_floricica 6y agoI should wait for the next parts, but I fear the author ignores our very important point of view: we are bayesian machines working with limited information under conditions of bounded rationality. Lack of proof that Vitamin D supplementation is necessary is irrelevant. We don't work on proofs. If I were to describe our standard, it would a balance of "might it help?" and "might it hurt?". Currently, and I think taking the next parts in consideration as well, I think the answers will be very much in favor of supplementation - with caveats I'm actually very eager to read about.
- devaboone 6y agoThanks for commenting! I wrote the blog, and I like your point of view. There was only so much I could cover in one post, but I do hope to get to these issues. And you are right, for most people the conclusion will likely be that a moderate dose of Vitamin D is not likely to harm, and may help - but then there are many many arguments over what constitutes a moderate dose, and I hope to cover that as well.
- bronlund 6y agoFor those who hasn't seen this already: https://www.youtube.com/watch?v=HH1rB-Ya2UQ https://www.youtube.com/watch?v=HH1rB-Ya2UQ What she says about dosage is especially interesting.
- Threeve303 6y agoHopefully part 2 will contain a section about how Vitamin D regulates cytokine production in your lungs. Without enough vitamin d, your body over reacts to a respiratory illness by over producing cytokines, and then the patient has a much higher chance of dying. There has to be additional evidence showing a decline in vitamin D levels over the past 20 years or so as we all got addicted to our devices, became narcissistic and anti social as a result of social media addiction, and largely stayed inside more than we used to. So we cut off our main source of vitamin D over time, and here we are...
- devaboone 6y agoCytokine production wasn't something I was able to include, simply because I was trying to cover a lot of ground in 1200 words! I alluded to it in the discussion about the cascade of events that occur when Vitamin D binds to immune cells. Cytokine production is one of those events. Still, I'm not completely convinced that Vitamin D deficiency directly leads to a higher chance of dying due to cytokine production. It's another one of those areas where we have a correlation, and a plausible explanation for causation... but it's not straightforward. And yes, the lack of sunlight is one explanation for why we seem to have so much Vitamin D deficiency... then again, maybe we see so much because we are defining deficiency the wrong way. There are so many things to discuss, and hopefully I can get to all of them.
- Threeve303 6y agoI'm just a software developer and simply regurgitating stuff I've read and maybe only half way understand. I look forward to someone like you with an open mind and with the proper knowledge to tackle that specific question. Thanks!
- AtlasBarfed 6y agoI am shocked that knockout of vitamin D receptors still produced a functioning organism given how important vitamin D has been billed.
- sradman 6y ago> Obesity, for example, is a known risk factor for diabetes, and people who are obese also tend to have low Vitamin D levels, due mostly to the dilution of the fat-soluble vitamin in the larger mass of adipose tissue. I didn't know this. I'm hoping that Part II addresses the long-term Vitamin D storage mechanism. Logically, since sun derived Vitamin D is accumulated during the summer and depleted during the winter, extra storage capacity might be beneficial. This is one area of research where the seasonal cycles are critical. Latitude and the date that samples are collected should be part of the dataset. Since diet and lifestyle seems to be involved, I wonder how much the phytate [1] content of the starchy staples we consume contributes to Calcium/Magnesium imbalances: > The (myo) phytate anion is a colorless species that has significant nutritional role as the principal storage form of phosphorus in many plant tissues, especially bran and seeds. It is also present in many legumes, cereals, and grains. Phytic acid and phytate have a strong binding affinity to the dietary minerals, calcium, iron, and zinc, inhibiting their absorption. It would be ironic if white rice and white bread become recommended over high fiber options. I wonder if the detrimental effects of phytates only apply during digestion, suggesting that some foods shouldn't be mixed in the same meal, or whether the binding affinity is something that occurs in aggregate independent of ingestion time. [1] https://en.wikipedia.org/wiki/Phytic_acid https://en.wikipedia.org/wiki/Phytic_acid
- ibigb 6y agoFor a review of many vitamin D studies google "site:theincidentaleconomist.com vitamin d", a blog by a doctor who evaluates many studies. Many do not show extra vitamin D beneficial. Blog quoute: " The IOM says that anything over 20 ng/mL is “Generally considered adequate for bone and overall health in healthy individuals” and when you get over 50 ng/mL “Emerging evidence links potential adverse effects to such high levels”. I do not understand why we keep looking for Vitamin D to be some sort of wonder drug. It’s seriously baffling to me." So we need some,>20ng/ml but keep it under 50 ng/ml.
- wtetzner 6y agoI suspect it's less that Vitamin D is a wonder drug, and more that the majority of the population (at least in the US) has a Vitamin D deficiency.
- aazaa 6y ago> Vitamin D is a big deal. Recent studies have shown that patients with low Vitamin D levels are more likely to die from Covid-19 than their Vitamin D-rich counterparts,(1) and deficiency in the vitamin has been linked to seven of the ten leading causes of death in the U.S.(2) 1,500 or so words about Vitamin D, but not a single mention of UV? Can the correlation between COVID-19 mortality and lack of Vitamin D be explained by lack of exercise and/or exposure to UV? In other words, maybe Vitamin D levels have nothing to do with the disease. It's just a marker for inactivity, which is the real culprit. If true, this explanation suggests that pumping people full of Vitamin D in the hope they'll fare better with certain diseases would be about as useful as force-relocating the homeless to Beverly Hills. Correlation, not causation. The paper cited by the author (1) doesn't consider this possibility, either.
- throwawaye3735 6y agoi was reading another thread where people were saying homeless and surfers, people who spend a lot of time outside, often have low vitamin D when they get tested. I have NO idea how true that is, but might be an interesting data point.
- elric 6y agoI can't vouch for the veracity of this claim, but I once read somewhere that it takes a while for the vitamin D, which is apparently created in the upper layers of the skin, to work its way down into the bloodstream, and that if you spend a lot of time in the water, it doesn't make it through. Maybe because being wet a lot tends to dehydrate the skin? I don't know.
- mikestew 6y agoHow much skin is exposed when wearing a wet suit? There's your answer. Just depends on whether the study took place in California (which has chilly water) or Hawaii (which doesn't).
- kyawzazaw 6y agocheckout the episode of RadioLab
- corpMaverick 6y agoVitamin D also helps Cluster Headache. A Survey of Cluster Headache (CH) Sufferers Using Vitamin D3 as a CH Preventative https://n.neurology.org/content/82/10_Supplement/P1.256 https://n.neurology.org/content/82/10_Supplement/P1.256
- InInteraction 6y agoI've recently posted 2 Vitamin D studies on HN. One "COVID‐19 and Vitamin D" study recommends treatment of COVID‐19 patients with high dose of vitamin D - 200,000 IU of vitamin D2 or vitamin D3 when admitted with COVID-19 followed by 4,000-10,000 IU/day - since populations most vulnerable to COVID-19 are likely vitamin D deficient (https://news.ycombinator.com/item?id=24132440 https://news.ycombinator.com/item?id=24132440) Another study (cited by Deva Boone) discusses Vitamin D deficiency is a predictor of poor prognosis in patients with acute respiratory failure due to COVID-19: 81% of patients had hypovitaminosis D; severe vitamin D deficiency patients had a 50% mortality probability, while those with vitamin D ≥ 10 ng/mL had a 5% mortality risk (https://news.ycombinator.com/item?id=24109396 https://news.ycombinator.com/item?id=24109396)
- pmarreck 6y agowhy are all the images in this article blurred beyond all recognition?
- viburnum 6y agoCan’t find it now but I remember seeing something about how people with not enough zinc in their diet will have low D, even if they supplement or get sunshine. So maybe low D is a symptom of some other problem upstream.
- kpfleger 6y agoThis piece is not as thorough as my vitamin D & COVID-19 review: http://agingbiotech.info/vitamindcovid19/ http://agingbiotech.info/vitamindcovid19/ or its 1-page bullet-point summary: http://agingbiotech.info/vitamindcovid19facts/ http://agingbiotech.info/vitamindcovid19facts/ A lot of words on correlation != causation without noting any of the causal evidence. Even my 1-pager highlights the obvious responses to this over-used inequality: 1. RCTs show D supplements effective against respiratory infection (Martineau BMJ'17: 25 RCTs, now updated as preprint expanded to ~40RCTs covering ~30,000 people. 2. Causal evidence D is protective against lung injury (in rats) related to ACE2. 3. D extends lifespan in worms (which don't have bones), and we all know how much of a risk factor age is for C19. [This one not in my 1pager, only the full review.] 4. The number of plausible biological mechanism arguments is very large and expanding. See Linda Benskin's excellent review for the most comprehensive review of that evidence up through mid-June. More recently, the active form has been shown to have direct action against SARS-CoV-2. 5. Causal inference model shows that D's effect on C19 is causal [Davies et al]. 6. Mendelian randomization shows that the correlations that would need to explain its data are far fetched (eg, systematic racism is worse in the US the farther north you go, by more than 5x) [De Smet et al] 7. Controlled intervention trial shows benefit from D+mag+B12 [Chuen Wen Tan et al] I don't talk about it in my reviews, but there is also a set of guidelines for when you can infer causation from observational data called Hill's criteria and one paper did apply that to D related data and the evidence so far met all the criteria. Long pieces that try to create uncertainty around vitamin D in the context of COVID-19 by repeatedly questioning the correlational data without noting any of the relevant causal evidence are far too common these days, and a bit irresponsible at this point. Karl
- kpfleger 6y agoCorrection (sorry, copy/paste error): The Mendelian randomization paper was by Kohlmeier. De Smet was one of the other studies.