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The Big Vitamin D Mistake

ncbi.nlm.nih.gov

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Re: The Big Vitamin D Mistake

#271

Post by chrisbennet »

Spooky23 wrote: post #207
LeifCarrotson wrote: post #172

Earlier quoted context omitted.

Fair skin is a lot better than skin cancer!

People who work outside don’t get skin cancer. People who cook themselves for fun do. If they did, we would know, because workers compensation would be paying for it.

Yes, they do. My father, a life long outsdoorsman and forest ranger for many years regularly had/has skin cancers removed once he got into his 70's. The cancer causing sun damage from your youth/working years doesn't tend to catch up with you until you're older I believe.

Re: The Big Vitamin D Mistake

#272

Post by 52-6F-62 »

hyperpape wrote: post #236
seanmcdirmid wrote: post #226

Earlier quoted context omitted.

Supposedly this is why Northern Europeans evolved lactose tolerance. Asians got the D they needed from the sun and leafy veggies.

Lactose tolerance evolved in several different populations independently (including African populations), so I think Vitamin D can only be part of the story. Lactose tolerance gives you access to nutrients from milk, which has a huge impact.

I don't know any of the history, but I would wager high protein content as that's also the huge benefit meat-eating brought humans.

Re: The Big Vitamin D Mistake

#273

Post by logfromblammo »

floatingatoll wrote: post #195
jhwhite wrote: post #178

Could someone help me understand this? >it was found that 8895 IU/d was needed for 97.5% of individuals to achieve values ≥50 nmol/L. Another study confirmed that 6201 IU/d was needed to achieve 75 nmol/L and 9122 IU/d was needed to reach 100 nmol/L. The largest meta-analysis ever conducted of studies published between 1966 and 2013 showed that 25-hydroxyvitamin D levels What is IU/d? What is nmol/L? Could someone EL…

The generally accepted goal by both the researchers and the US RDA is to reach 50-75 nmol/L blood levels, using however many IU that takes. IU/d is "IU per day of Vitamin D", and nmol/L is "nmol per liter of blood". Vitamin D is measured in IU rather than grams like most other supplements for medical reasons I'm not familiar with. nmol is an unfamiliar unit, but I can help clarify why this paper is so stunning anyway…

IU are used whenever a particular vitamin has multiple forms with varying levels of efficacy [0]. Or it may be used when the typical quantities are measured in inconveniently small units.

1 IU of cholecalciferol is 0.025 micrograms. If you supplement vitamin D at hogh doses, make sure you use cholecalciferol rather than ergocalciferol. The former is naturally synthesized in your own skin, whereas the latter is produced mainly in mushrooms, and can result in unpleasant side effects. Maximum-dose recommendations from nutritionists may include the assumption that the consumer does not know the difference, therefore reflect the highest safe dose of the least-safe vitamer.

It is similar to the issues with vitamin A, when someone may safely supplement with carotenes and unsafely supplement with retinol. You can eat sweet potato and carrots until you turn orange, but you cannot eat a single bite of polar bear liver. But because we are mostly idiots, nutritionists cannot recommend a high-dose supplement for vitamin A, with carotene in mind, because someone will inevitably overdose themselves with retinol. So if you can certify yourself as not-a-moron, you will be able to figure out when those recommendations may be safely ignored.

[0] https://en.wikipedia.org/wiki/Vitamer

Re: The Big Vitamin D Mistake

#274

Post by BeetleB »

I see a number of comments about taking Vitamin D for mood and SAD issues.

My goto site for supplements is http://www.informationisbeautiful.net/visualizations/snake-o...

It essentially ranks supplements based on the amount of research there is to support the claim (so the same supplement can show up in multiple categories). You can see Vitamin D is backed by a lot of research for various ailments, but the category for which there is least evidence is mood related disorders.

On a side note, be very wary of the supplements you take (in the US). There is virtually no oversight in their manufacture, and various groups' investigations have shown that the claimed dosage can be way, way off. And the inactive ingredients may be false as well. Relying on well known companies did not seem to make a difference.

I recall an interview with a pharmacist at a hospital that had decided they test the supplements they had in stock - given that they were giving them to patients. They were rather shocked.

If anyone has a good resource where a group tests different manufacturers' supplements and has some kind of reliability rating, I'd love to know. I pretty much stopped taking supplements when I saw how unreliable the claimed dosages were.

Re: The Big Vitamin D Mistake

#275

Post by lostlogin »

coldtea wrote: post #253
LeifCarrotson wrote: post #172

Earlier quoted context omitted.

Fair skin is a lot better than skin cancer!

Sun exposure != skin cancer. It's like avoiding eating food altogether because you might became obese, or worse (given the odds) choke on it.

When the time it takes to get a burn is 10 minutes or less, you might as well treat it as exposure = burn.

Re: The Big Vitamin D Mistake

#276

Post by micro_cam »

madhadron wrote: post #234
micro_cam wrote: post #50

This article seems to be a low quality review of other research with a clickbatey title (full text here: https://www.jpmph.org/journal/view.php?doi=10.3961/jpmph.16.... ). Pubmed is sort of like arxiv.org and the fact this has an nih.gov base url should not be taken as an endorsement of it by the NIH. That said I do actually believe that more then the recommended amount of vitamin D can be beneficial and the recommen…

I logged in just to downvote this. PubMed is an aggregator, closer to Google Scholar than the arXiv.

Fair enough. I was just trying to make the point that something being on pubmed doesn't mean its anything close to an NIH recommendation and chose arxiv as it would be familiar to a CS audience.

Re: The Big Vitamin D Mistake

#277

Post by skybrian »

theprotocol wrote: post #138
skybrian wrote: post #103

Earlier quoted context omitted.

It's not a study. It's an article that cites other studies.

It has an abstract, so I figure it's a meta-analysis and not just an article.

It's not a meta-analysis either. It cites a meta-analysis, which has different conclusions.

Re: The Big Vitamin D Mistake

#278

Post by zeveb »

deepGem wrote: post #111
King-Aaron wrote: post #37

Anecdotally, I had this discussion with a cardiovascular interventionist specialist about seven or eight years ago when I was managing a team of cardio theatre orderlies in a private hospital. He made the comment, "mark my words, in about five to ten years time there will be a major scare about needing to absorb more vitamin D". His opinion was that the increase in sunscreen usage and the push to avoid skin cancer by…

The NIH guys also did a study that said that even in tropical countries, Vitamin D absorption has fallen dramatically because of lifestyle changes. One of the probable factors is the lust for fair skin. I routinely see people covered from head to toe to help them stay fair skinned, even kids are sent to play covered in full sleeve clothing. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3897581/

> One of the probable factors is the lust for fair skin.

I think this must be cultural. Certainly in my experience in the United States, the lust is for tanned skin. There are even tanning salons, where one can lie down in a machine which floods one's skin with UV.

Now, I personally love fair skin, and have never understood why others seem to love a tan so much.

Re: The Big Vitamin D Mistake

#279

Post by jessaustin »

kgwgk wrote: post #212
Spooky23 wrote: post #207

Earlier quoted context omitted.

People who work outside don’t get skin cancer. People who cook themselves for fun do. If they did, we would know, because workers compensation would be paying for it.

Don't they? "However, compared with the general population, the rates for certain diseases, including some types of cancer, appear to be higher among agricultural workers, which may be related to exposures that are common in their work environments. For example, farming communities have higher rates of leukemia, non-Hodgkin lymphoma, multiple myeloma, and soft tissue sarcoma, as well as cancers of the skin, lip, stom…

Ag workers were routinely exposed to ridiculous levels of dangerous pesticides for most of the 20th century.

Re: The Big Vitamin D Mistake

#280

Post by micro_cam »

AstralStorm wrote: post #116
micro_cam wrote: post #50

This article seems to be a low quality review of other research with a clickbatey title (full text here: https://www.jpmph.org/journal/view.php?doi=10.3961/jpmph.16.... ). Pubmed is sort of like arxiv.org and the fact this has an nih.gov base url should not be taken as an endorsement of it by the NIH. That said I do actually believe that more then the recommended amount of vitamin D can be beneficial and the recommen…

If taking EPIC series morbidity and mortality endpoint analysis at face value, best outcomes on average are around 2500 IU/d intake. (In generally healthy individuals.) So this recommending 4000 IU/d is not too far fetched.

Yeah to be clear I think there is lots of good science supporting increased vitamin D intake possibly including some of the work cited/described here. This article just doesn't seem notable, novel or particularly well written beyond the grabby title.
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