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The Big Vitamin D Mistake

ncbi.nlm.nih.gov

441–450 of 459 posts

Re: The Big Vitamin D Mistake

#441

Earlier quoted context omitted.

>>Pubmed is sort of like arxiv.org What? It's nothing of the sort. Pubmed is not a preprint server. The paper in question was accepted by a journal. The quality may not have been great - I agree - but it is not like the archive at all.

He means it’s a resource for finding any/all articles, irrespective of source journal or quality - specifically pointing out that people shouldn’t infer anything from the NIH url. It’s very much like arxiv in that regard.

Seems that way, I know, to some of my friends who don't work in the same field as me (health research), but pubmed doesn't include all biomedical journals, and it's not a place where anyone can archive papers independently. Which isn't to say that everything in pubmed is high quality or that it's a great gatekeeper, but yeah, it definitely excludes material.

Re: The Big Vitamin D Mistake

#442

Earlier quoted context omitted.

I've known about the sunscreen misinformation for a long time. My dad died of malignant melanoma. He wore sun screen all the time. He didn't swim. He would wear sun hats. He was paranoid, and likely had premonition of it. Unfortunately, his prevention methods might have actually exacerbated his odds even further because he was depriving his skin of one of its few natural healing modalities.

I'm sorry to hear you dad died of melanoma. But I can guarantee that reducing his UV exposure did not increase his risk. It's possible that intense and closely repeated sun exposure as a child had already caused DNA damage. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3409870/ Anyway, please wear shades and a hat.

You're right, my father had bad sunburns as a child. Shades and hat are a good tip, as is reducing UV over-exposure.

My point is that moderate sun exposure is healthy and good melanoma prevention. From what I've seen, there is quite a bit of research to back this up.

I think that better education about this would encourage people to develop healthy relationships with the sun at a young age. Right now the conventional wisdom seems to be "just throw sunscreen at it" / "stay out of the sun unless you are wearing sunscreen" and I think this totally misses the point.

My caution is that it's unwise to tell people to avoid sun exposure in total. While sunscreen does seem to be helpful in slowing sun damage, it'd also be unwise to suggest that sunscreen will protect people from overexposure, there isn't really evidence for that. There is a whole body of research. Take a look at some of the studies cited in this article http://m.jabfm.org/content/24/6/735.full

Re: The Big Vitamin D Mistake

#443
post #432

Earlier quoted context omitted.

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 produc…

Where can one go to learn about different forms of vitamins and the safe&recommended doses for each?

Unfortunately, most of the sites that claim to aggregate such information are heavily incentivized to misrepresent or falsify information in order to sell you supplements, either directly sourced or through affiliate programs.

Many of the remainder are constrained by politics or medical malpractice law. For instance, USRDA recommendations and USDA gimmicks like the food pyramid are heavily influenced by agricultural businesses. Minimum daily requirements are mostly based on the amounts needed to avoid showing symptoms of known deficiency diseases, rather than to actually be healthy.

The actual scientific research is rather sparse. I am aware of a study performed in the 1960s that completely replaced all meals with a nutrient slurry with the texture of corn syrup, which was partially spoiled because subjects were convincing accomplices to smuggle real food to them. Thanks to subject compliance issues, most long-term research is done on analysis of food-diary observations and surveys. Short-term research, such as for satiety and glycemic response, is more controllable.

You will have to do a lot of your own digging.

Start with professional athletes like swimmers, cyclists, and bodybuilders, but beware the "broscience". Look at the life extension people that use caloric restriction and intermittent fasting. Check out the Soylent people. Look at the practice of geophagy. Listen to some vegans. Study some biochemistry, especially the Krebs cycle and the known DNA repair and disease-fighting mechanisms. Do a lot of Wikipedia walks.

Be aware that your nutrient requirements will vary from others as a result of your personal genetic quirks, but mostly can be expressed as a ratio of mass to ingested kcal.

Learning the biochemistry is key. You have to know that omega-3 and omega-6 fatty acids use some of the same enzymes at particular steps in their metabolic chains, so those fats will compete with one another in your body, meaning that those nutrients must be in a balanced ratio to each other, regardless of your absolute consumption. What's the best ratio? I don't know. Cursory analysis suggests that 6 parts omega-6 to 1 part omega-3 is too high. Supplementing with krill oil, algae oil, chia seed, or flax meal would therefore be as warranted as cutting the amount of omega-6 from vegetable oils.

If you look at Na+/K+-ATPase, it actively transports sodium and potassium across the cell wall until the interior is mostly K and the exterior is mostly Na. Your dietary requirements are likely related to the homeostasis mechanisms for regulating the ionic concentrations. What's the best ratio? I don't know. Cursory analysis suggests that your body requires overall 2.25 times as much K+ as Na+ at any given time, but the K+ is more strongly conserved, being mainly inside your cells. So you should probably eat a ratio similar to that found in your extracellular fluid, which is 33.5:1 Na+:K+, which indicates that your table salt should probably be at least 1:24 KCl:NaCl by mass. Sea salt provides some K, but not that much--about 1:200. And it also shouldn't be more than 3:1 KCl:NaCl by mass, even if you are severely deficient, because your body needs the Na+ to be present to pump K+ into the cells.

It's all guessing, and the signal-to-noise ratio is very low.

Re: The Big Vitamin D Mistake

#444

Earlier quoted context omitted.

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.

Lots of people in health research do treat pubmed as a gatekeeper though (sometimes foolishly imo). It is more exclusive than both Google Scholar and arxiv -- but also like you say, not a guarantee of quality + not the kind of resource where you can read one article and be like "here's what NIH says."

So semantics, I guess. Just felt compelled to mention it, probably more because it frustrates me to see health researchers use pubmed as their only gateway to scholarly lit.

Re: The Big Vitamin D Mistake

#445

Earlier quoted context omitted.

There is misinformation about sunscreen. I'm not going to go and advocate that people don't use sunscreen, rather, for my own self, I've decided that it's important to have positive, moderate exposure to the sun in order to develop a healthy tan, to avoid overexposure, and to use sunscreen and protective clothing if I'm sure to be out in heavy sun. It's a complex, dynamical issue and there is conflicting evidence abo…

It's going to take a lot to convince me, at 56 and very aware of sun damage to the skin of my friends who spend more time in the sun than I do, that "healthy tan" isn't an oxymoron.

"Tan" doesn't necessarily mean that someone got that tan through healthy sun exposure.

Check out JoeAltmaier's comment.

If you spend some time in the sun without getting a tan, it's still good for you even if you don't tan, as long as you're not burning.

Re: The Big Vitamin D Mistake

#446

Earlier quoted context omitted.

Where do you live? I suspect it isn’t in the South Pacific.

In Southern Europe and SE Asia. Does that count?

No for Europe but closer for SE Asia. The South Pacific is worse due to the ozone hole which mainly effects regions below the equator. It has a savage effect on UV that gets through. Obviously a bad year, but check the below image and you’ll get the idea of the pattern.

https://www.livescience.com/46701-andes-highest-uv-index-mea...

Re: The Big Vitamin D Mistake

#447

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 f…

For me Examine.com is the best source on supplements/vitamins take for example Vitamin D https://examine.com/supplements/vitamin-d/ as for your question regarding Supplement manufacturers test check labdoor https://labdoor.com/

Looking at Vitamin D on Labdoor:

>6 of the 19 products in this report exceeded their label claims by greater than 40%.

>All 19 vitamin D supplements met or exceeded their claimed vitamin D3 content, ranging from +0 to +900.0 IU versus their stated label claims.

>The average label variance in this testing batch was 22%.

Wow.

Let's look at melatonin:

>Only half of the products tested (15 of 30) measured melatonin levels within 10% of their label claims. 7 products deviated from their claims for melatonin by at least 25%. 3 of those products recorded 40% or more melatonin than their label claims, and 1 product had less than 1% of its label claim for melatonin.

Vitamin B12:

>Overall, vitamin B12 measurements in this batch analysis ranged from 515 mcg to 6990 mcg per serving, deviating from label claims by an average of 27%. 3 products also recorded vitamin B6 and/or vitamin B9. 9 of the 13 products recorded more vitamin B12 than claimed, with one product recording as much as 74% of its label claim for vitamin B12. All products passed heavy metal screenings, and recorded vitamin B12 levels considered to be safe by the Institute of Medicine (IOM)1.

Re: The Big Vitamin D Mistake

#448
I think that vitamin D defficiency may have contributed to start of my Multiple Sclerosis! I used to sit mostly inside all summer programming. So be careful.

Re: The Big Vitamin D Mistake

#449
post #23

This supports my lived experience. Found to be incredibly low in vitamin D, and diagnosed with autoimmune thyroiditis. Doctor said to supplement with 2000 IU being the max per day. After seeing no improvement whatsoever in vitamin D levels, and after talking with others with the same issue, I self medicated to 10000 IU / day. Lo and behold my vitamin D levels went back up and my auto-antibodies went back down.

This is similar to my lived experience. I was diagnosed with Hashimoto's 3 years ago. I was lucky to find a great doctor that specialized in it. He put me on 15000 IU / day for 3 months because I was so severely low in addition to having high antibodies. Within 3 months my levels were so much better. I still take 10000 IU / day along with selenium, iron, fish oil and good diet/exercise and all my levels have been in…

Could you write a bit about the role of selenium in your treatment? Thanks.

Re: The Big Vitamin D Mistake

#450

Earlier quoted context omitted.

From the last couple sentences of the abstract: This could lead to a recommendation of 1000 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. So 8000 IU for adults

Interesting. I started taking it since I've started working inside for my day job. Apparently I should be upping my dosage. I take a multi and one or two D tablets and probably get a max of ~5600 from that outside of any absorbed from foods. I also eat a lot of eggs. My girlfriend will be pleased to know that I'll be upping our egg intake!

Better watch out with egg intake upping, check your cholesterol and trigliceride levels. Anyway good to consult with professional nutrituonist.
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