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The Big Vitamin D Mistake

ncbi.nlm.nih.gov

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Re: The Big Vitamin D Mistake

#311

Post by Malic »

amelius wrote: post #295
netcraft wrote: post #262

Earlier quoted context omitted.

This is per day? I have been deficient for a few years now and I take ~6000 IU per day, but it doesnt seem to make a big difference in my blood tests. I already thought 6K was a lot...

Are you taking it with food? I think it dissolves in fat, so you might want to take it with some oil for better absorption.

Yup - it's a fat soluble vitamin - this is a very good point to bring up. I made the "taking it with my low fat meal of the day" (breakfast) and made a change to correct that.

Re: The Big Vitamin D Mistake

#312

Post by kaybe »

lostlogin wrote: post #275
coldtea wrote: post #253

Earlier quoted context omitted.

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.

After I met an albino woman travelling I really appreciate my very-white-but-not-albino-skin.

Sun lotion can only prolong your safe time, but 0 times whatever is still zero, as in her case. So there is a difference.

Re: The Big Vitamin D Mistake

#314

Post by exhilaration »

ptero wrote: post #305
exhilaration wrote: post #193

Earlier quoted context omitted.

Except during the summer months, the skin makes little if any vitamin D from the sun at latitudes above 37 degrees north (in the United States, the shaded region in the map) or below 37 degrees south of the equator. People who live in these areas are at relatively greater risk for vitamin D deficiency. Check out the map: https://www.health.harvard.edu/staying-healthy/time-for-more...

I saw the quoted text, but missed any explanation. I would love a clarification on whether they claim the skin is not getting exposed to sun or, even when exposed, does not make any vitamin D, which is how I read the above. This is an honest question -- if it is the first, I am not too concerned. I grew up in a colder climate and, while living far in the shaded area today, routinely wear short sleeves and walk a lot…

The sun is too low in winter and the atmosphere blocks the UVB rays our skin needs to produce Vitamin D. The same thing happens around sunrise and sunset even in summer. Here's a good explanation from HN's favorite site:

https://physics.stackexchange.com/questions/268509/why-is-th...

Re: The Big Vitamin D Mistake

#315

Post by appleiigs »

themodelplumber wrote: post #249
jciochon wrote: post #95

Earlier quoted context omitted.

This is interesting and resonates with me. While I agree with your conclusion about giving advice, could you perhaps share your methodology for discovering your triggers?

Every negative episode I deal with gets tracked and logged. I have a notebook just for this purpose, I time stamp my results, and I try to develop my own theories of what might be going on, and what might have happened, while remaining open to trying others' ideas (that's how I found out about sleep cycles, dopamine, etc.). My purpose is to develop a framework which gives me greater leverage against the suffering. Wh…

Your tracking reminds me of the book Eloquent Javascript. A chapter walks through a story where a guy would turn into a squirrel every night and he doesn't know why. He tracks everything and run correlations on it to find a cause. http://eloquentjavascript.net/04_data.html

Thanks for sharing your methods... very proactive and persistent.

Re: The Big Vitamin D Mistake

#316

Post by coldtea »

lostlogin wrote: post #275
coldtea wrote: post #253

Earlier quoted context omitted.

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.

That's when sunbathing on Venus. Or if you're a ginger or similar.

On good old Earth, one can sit in the sun for hours on end without a burn. In fact people frequently do, like all the time.

Re: The Big Vitamin D Mistake

#317

Post by kaybe »

baq wrote: post #180
pcarolan wrote: post #175

Earlier quoted context omitted.

What dose is recommended for adults and what is the best way to get it into your system?

an hour of sunshine a day?

And here's a calculator:

https://fastrt.nilu.no/VitD-ez_quartMED.html

They calculate to 1000 UD if I see that right, I assume it's linar over time so just multiply that.

Re: The Big Vitamin D Mistake

#318

Post by dsr_ »

zeveb wrote: post #278
deepGem wrote: post #111

Earlier quoted context omitted.

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.

It's a cultural thing, and directly related to wealth (or class, if you prefer).

If most people work outside for a living, then the sign of wealth is that you don't have a tan. If most people work in offices, then the sign of wealth is that you have a tan, implying that you went on vacation or otherwise have the available leisure time.

When most people do manual labor, having impractically long fingernails demonstrates that you don't have to do that.

When most people have two or three sets of clothing, changing clothes several times a day demonstrates your wealth.

When most people eat a subsistence diet, being fat is demonstrating wealth. when most people eat fast food, being thin demonstrates your superior resources.

If most people need to pay attention to what they are wearing at their jobs, dressing in a way which signals that you don't have to pay attention is a status marker.

If everybody drives a car, picking an unusual vehicle can be a status marker. What's the difference between a Chevy Silverado 2-door and a Ford F-150 SVT Raptor? They demonstrate different spending priorities.

Re: The Big Vitamin D Mistake

#319

Post by throwawayjava »

alex_stoddard wrote: post #291
drostie wrote: post #256

Earlier quoted context omitted.

I mean, it does. The "fairy tale" that one hears in high school doesn't, but we put aside fairy tales when we became adults. If you are done with the "undergrad level" of Popper and Kuhn it is worth reading Imre Lakatos's work on philosophy of science. It contains a moment where one realizes that research programs live or die by this "impact factor" and that this living or dying is a key part of the overall methodolo…

But to stretch the analogy a bit further would it be fair to say that impact factor is very like sexual selection for extreme display traits that otherwise are detrimental to the wellbeing of the species? Yes impact factor matters to current science as practiced but there is plenty of good criticism to show (at least as it is currently calculated) that it is a lousy measure of what is likely to end up being true, rep…

> would it be fair to say that impact factor is very like sexual selection for extreme display traits that otherwise are detrimental to the wellbeing of the species?

If I read every PoS article vaguely related to my research, I'd never get anything done. In practice, I don't pay attention to impact factor. But I do pay attention to who's publishing. And that's basically the same as impact factor, in practice.

> that it is a lousy measure of what is likely to end up being true, reproducible and useful.

I don't think so.

High impact factor publications are MUCH more likely to be quality science than low impact factor publications (at least in my area).

The major venues would have to get at least two orders of magnitude worse before they became bad indicators of quality.

Of course, and obviously, that does not entail that all work published in high impact factor journals is high-quality.

I think the fundamental problem is just that you vastly under-estimate the enormous volume of utter crap there is out there.

Re: The Big Vitamin D Mistake

#320

Post by tomatsu »

52-6F-62 wrote: post #269
edraferi wrote: post #257

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!

> Apparently I should be upping my dosage.

Get your current nmol/L value and decide based on that data.

In Germany, you have to pay around €30 for that test. It's not covered by insurance for some reason. Anyhow, if they ask for significantly more than that, they are ripping you off.

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