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The worthlessness of Vitamin D is mildly exaggerated

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Re: The worthlessness of Vitamin D is mildly exaggerated

#301

Post by trevorkoob »

rzz3 wrote: post #19

Has anyone done a RCT of D3+K2? K2 seems to be important in the absorption of D3. Another aspect that bothers me with these studies is that we’re simply supplementing the vitamin D, seemingly without measuring the change in blood levels. I took 2000IU (+K2) a day for many years in between testing my blood levels and still had <30ng/ml and had to go up to 5000IU/day. I’d like to see some further study.

When I did my master's thesis on Vitamin D supplementation the conclusion was that vitamin D testing is wildly inaccurate, and we needed to have studies based on a target level - ideally one based around sub-saharan African community levels.

As for supplementation, sunlight has been estimated at providing up to 20,000IU per day, which I think (not medical advice due to the lack of study), from a mechanistic point of view, suggests an upper limit to daily supplementation.

Re: The worthlessness of Vitamin D is mildly exaggerated

#302

Post by trevorkoob »

redrove wrote: post #281
nullbio wrote: post #278

Vitamin D is a biomarker of a process that happens in the body that is beneficial for longevity. This biomarker is created in response to receiving sunlight. The synthetic vitamin itself, does little, if anything, for your health. The process of receiving the sunlight is what benefits your health. This applies to a lot of other vitamin supplements as well. So whilst you may be able to take a supplement to boost your…

Do you have any sources for this? Genuinely interested in reading more.

One interesting aspect of Vitamin D that is not regularly discussed is the photo-isomerization of Vitamin D into inactive isomers in the skin.

I think of it similarly to Beta-Carotene, in that consuming the "natural source" has no known toxic amount, while consuming processed vitamin A can be toxic in large doses.

Increasing sun exposure will not raise blood vitamin D metabolite concentration indefinitely, and we don't have good studies that accurately measure the amounts of Vitamin D and its photo-isomers and their concentration in relation to large doses of UV exposure.

Therefore, through sun exposure, people may be storing large doses of Vitamin D isomers in their skin, keeping their levels much higher than typically prescribed oral supplementation levels.

Re: The worthlessness of Vitamin D is mildly exaggerated

#303

Post by joehabeebs »

toxicdevil wrote: post #171
joehabeebs wrote: post #168

I was told I was Vitamin D deficient and accidentally over indexed on supplements and got quite sick. Some of the dosages on OTC are ridiculously high

A different personal experience. I had Vit D deficiency. Started on 2000IU per day and was still deficient after months. Then started on 5000IU per day, initially daily but now every other day or so. My last test was in the middle of the "normal" range. I have been taking VitD for 4 years or so. A lot of my symptoms like tiredness, sleepiness etc have improved since then. I asked my immediate family members to do a t…

I was also taking 5K IU per day but had to tone it down after getting quite dizzy. I've been taking them every few days now and have yet to do a follow up but this is helpful to hear!

Re: The worthlessness of Vitamin D is mildly exaggerated

#304

Post by zhivota »

jerlam wrote: post #159
zhivota wrote: post #132

Thousands of words and no mention of the obvious thing - testing whether sun exposure is beneficial or harmful. The article opens with the observation that southern states had lower cancer rates due to solar irradiance. But then we intervene by taking pills. Why not try to absorb through the skin, even if it means something like a tanning bed?

There are many nuances and people seem bad at understanding those. Too many are getting their information from "health influencers" and 30 second videos, which is why we seem to bounce between the two extremes of "everyone should take Vitamin D!" and "Vitamin D is overrated!". Australia has tried to explain sun safety here, taking into account that Vitamin D is best obtained from sunlight: https://www.cancer.org.au/c…

Yeah not bad, though UV index of 3 is pretty comically low. Here in Manila it's basically full cloud conditions.

I'd be interested to know a curve, i.e. at UV index 8, 3 minutes exposure, at index 6, 10 minutes exposure, etc. Maybe with a scaling for skin tone. It seems like either this kind of study has never been done (perhaps for ethical reasons) or else the information is not being disseminated. The latter seems to happen often in the medical space for paternalistic reasons, which honestly make sense for the broad public but it should be available for people to find who are motivated and have a deeper interest anyway.

Re: The worthlessness of Vitamin D is mildly exaggerated

#305

Post by tbugrara »

Aurornis wrote: post #7

This is a refreshingly balanced and honest analysis of Vitamin D studies. The strongest evidence for Vitamin D is in people who are severely deficient. Bumping up to a normal range can provide some improvements. The health influencers started noticing that the Vitamin D studies coming out weren't matching their original hype for Vitamin D, so many pivoted to trying to make claims that most people are severely deficie…

Mind sharing what "higher powered follow on" studies (not even sure what this means) showed less interesting results for omega3 supplementation?

Re: The worthlessness of Vitamin D is mildly exaggerated

#306

Post by chrisweekly »

bakul wrote: post #272
chrisweekly wrote: post #241

Earlier quoted context omitted.

"vegetarians" relevance?

Strict Vegetarians don’t eat eggs. No D vitamin fortified milk in his days. Many vegetarians don’t eat mushrooms, the only plant based source of vitamin D.

Interesting. Thanks.

Re: The worthlessness of Vitamin D is mildly exaggerated

#307

Post by bryanrasmussen »

da_chicken wrote: post #227
bryanrasmussen wrote: post #218

Earlier quoted context omitted.

Is it really less intense? When I go out on a sunny day in Denmark it is murder. When I go out on a sunny day in Italy it's generally just overall warm. At any rate another factor is that in the Northern regions it's my experience people do their best to soak up as much sun as possible.

I could believe that if you were near the coast. I grew up in central Michigan and thought the same about the sun until I spent a few years in southern Arizona. The sun there feels like a heat lamp in summer. The low humidity makes the atmosphere absorb less energy. Although it feels like it's about 5 C cooler than it actually is because sweat evaporates so quickly, but once it gets to 43 C you actually just feel vag…

In an American context, you're always near the coast in Denmark, in a Danish context, I think I still had this experience when I was living in Brønshøj, but yes the last decade I live near the coast, now I live 10 minutes away, but it's of course gotten hotter.

Re: The worthlessness of Vitamin D is mildly exaggerated

#308

Post by pocksuppet »

tremon wrote: post #149
NoPicklez wrote: post #120

Earlier quoted context omitted.

Come to Australia during the summer and watch how quickly you burn outside without sunscreen.

Yes, it's crazy to consider how far north Earth's entire land mass is skewed. Australia is basically the southernmost landmass (apart from Tierra del fuego), yet it is located squarely under the Tropic of Capricorn; at the same distance north of the equator (Tropic of Cancer), you've merely reached Mexico, the Sahara desert, and the Himalayas.

Most of Europe is at the latitudes of Canada. The whole UK is squarely north of Vancouver. https://vividmaps.com/comparing-latitude-of-europe-and-ameri...
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