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The Big Vitamin D Mistake

ncbi.nlm.nih.gov

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Re: The Big Vitamin D Mistake

#431

Post by XzetaU8 »

BeetleB wrote: post #274

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/

Re: The Big Vitamin D Mistake

#432

Post by Asooka »

logfromblammo wrote: post #273
floatingatoll wrote: post #195

Earlier quoted context omitted.

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 produc…

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

Re: The Big Vitamin D Mistake

#433

Post by angry_octet »

tomhoward wrote: post #428
kgwgk wrote: post #204

Earlier quoted context omitted.

Aren't those links about "people with naturally darker skin"? I'm not sure how cultural changes can affect that. Rich people may eat caviar, but eating caviar won't make you rich...

We know that genetics and environment both play a significant role. So think about it this way: If you're genetically predisposed to having very dark skin, you will be able to tolerate more UV exposure without significantly increasing your risk of cancer. And by continuing to be exposed to high UV levels, your body will continue to produce melanin to keep you protected. It's a feedback loop. If you're genetically pre…

The notion of 'building up a tan' is dangerously wrong advice. Even for people with darker skin it is unwise to have significant bursts of UV exposure.

I'm curious as to whether your educated guess derives from a clinical background, or reddit?

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2671032/

http://www.skincancer.org/prevention/skin-cancer-and-skin-of...

https://theconversation.com/amp/sun-damage-and-cancer-how-uv...

http://enhs.umn.edu/current/5103/uv/molelcularmech.html

Re: The Big Vitamin D Mistake

#434

Post by angry_octet »

blurbleblurble wrote: post #247
LeifCarrotson wrote: post #172

Earlier quoted context omitted.

Fair skin is a lot better than skin cancer!

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.

Re: The Big Vitamin D Mistake

#435

Post by angry_octet »

blurbleblurble wrote: post #408
jimjimjim wrote: post #381

Earlier quoted context omitted.

it's not misinformation. one anecdote in one direction does not counter thousands in the other direction. Talk to some people in the southern hemisphere (australia and nz). There is a LOT of awareness of sun damage in these countries.

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…

You are misrepresenting the studies findings. It did not show that sunscreen itself is ineffectual, but that as a population measure for children that it's effectiveness was variable. Anyone who has children will attest to the difficulty of applying and maintaining the required level of sunscreen, especially as it is invisible.

If you have concerns about the chemical sunscreens, please use zinc oxide. It is totally non reactive.

Sun damage is cumulative, a tan is a reaction to damage. People with a tan have sun damaged skin.

Naturally very dark skinned people are different, and also have enhanced mechanisms to allow damaged cells to self-euthanize.

Re: The Big Vitamin D Mistake

#436

Post by JoeAltmaier »

angry_octet wrote: post #435
blurbleblurble wrote: post #408

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…

You are misrepresenting the studies findings. It did not show that sunscreen itself is ineffectual, but that as a population measure for children that it's effectiveness was variable. Anyone who has children will attest to the difficulty of applying and maintaining the required level of sunscreen, especially as it is invisible. If you have concerns about the chemical sunscreens, please use zinc oxide. It is totally n…

Not quite right? A tan is a reaction to sunlight, independent of damage.

Ah! Research, gotta love it. UVA darkens directly as a result of action on the melanin. UVB damages DNA resulting in long-lasting production of more melanin.

Re: The Big Vitamin D Mistake

#437

Post by tomhoward »

angry_octet wrote: post #433
tomhoward wrote: post #428

Earlier quoted context omitted.

We know that genetics and environment both play a significant role. So think about it this way: If you're genetically predisposed to having very dark skin, you will be able to tolerate more UV exposure without significantly increasing your risk of cancer. And by continuing to be exposed to high UV levels, your body will continue to produce melanin to keep you protected. It's a feedback loop. If you're genetically pre…

The notion of 'building up a tan' is dangerously wrong advice. Even for people with darker skin it is unwise to have significant bursts of UV exposure. I'm curious as to whether your educated guess derives from a clinical background, or reddit? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2671032/ http://www.skincancer.org/prevention/skin-cancer-and-skin-of... https://theconversation.com/amp/sun-damage-and-cancer-how…

The notion of 'building up a tan' is dangerously wrong advice.

I know, I acknowledged that in my comment.

My main point was only about the extent to which people with genetically high melanin levels are at much lower risk of cancer (which your first link confirms), but how their risk might increase if their melanin levels drop.

I don't dispute that it's a complex and dangerous topic. And as someone with genetically very pale skin, I most certainly steer well clear of direct sunlight and make no efforts to develop a tan.

I'm curious as to whether your educated guess derives from a clinical background, or reddit?

That's a low blow :)

I rarely go anywhere near Reddit, certainly not for anything to do with health. I have spent 10+ years researching health topics for reasons to with serious, chronic, illnesses I've endured, and have now largely overcome thanks to what I've learned.

Re: The Big Vitamin D Mistake

#438

Post by angry_octet »

tomhoward wrote: post #437
angry_octet wrote: post #433

Earlier quoted context omitted.

The notion of 'building up a tan' is dangerously wrong advice. Even for people with darker skin it is unwise to have significant bursts of UV exposure. I'm curious as to whether your educated guess derives from a clinical background, or reddit? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2671032/ http://www.skincancer.org/prevention/skin-cancer-and-skin-of... https://theconversation.com/amp/sun-damage-and-cancer-how…

The notion of 'building up a tan' is dangerously wrong advice. I know, I acknowledged that in my comment. My main point was only about the extent to which people with genetically high melanin levels are at much lower risk of cancer (which your first link confirms), but how their risk might increase if their melanin levels drop. I don't dispute that it's a complex and dangerous topic. And as someone with genetically v…

It was a low blow. Sorry. I've been watching my uncle and father die slowly from melanomas, chunk by chunk cut out of their faces, their backs. My uncle still has a healthy deep tan.

And even last year I heard girls talk about building up a 'base tan' before summer. Roasting like rotisserie chickens under the solarium lamps.

Re: The Big Vitamin D Mistake

#439

Post by blurbleblurble »

angry_octet wrote: post #435
blurbleblurble wrote: post #408

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…

You are misrepresenting the studies findings. It did not show that sunscreen itself is ineffectual, but that as a population measure for children that it's effectiveness was variable. Anyone who has children will attest to the difficulty of applying and maintaining the required level of sunscreen, especially as it is invisible. If you have concerns about the chemical sunscreens, please use zinc oxide. It is totally n…

Right, it concluded "there is still no evidence of a protective effect of sunscreen against MN development in children". Melanocytic Nevi are precursors to melanoma, and childhood sunburns give people an early start in developing them.

Here's another study arguing that sunscreen might inhibit the inflammatory response without actually reducing the burn. Their abstract concludes "As such, sunscreens might promote instead of protect against melanoma." : http://journals.lww.com/melanomaresearch/Abstract/2005/02000...

SPF is actually measured by reduction of redness. That study points out that reduction of redness doesn't necessarily come with a reduction of damage!

If people are preventing their body from expressing its natural sun defenses and going out and overexposing themselves to the sun, believing themselves to protected... If that protection is illusory, that's kind of a recipe for disaster. People could be getting burned and not even know it... They won't even know to put aloe on.

Take that one with this one, which postulates that sun exposure isn't what causes malignant melanoma, sunburns are:

> Although there is convincing evidence that nonmelanoma skin cancer is related to cumulative sun exposure, there is less evidence of that association with CMM. If CMM were related to cumulative sun exposure, one would expect that outdoor workers would have a greater incidence of CMM than indoor workers. However, that is not the case. The incidence of CMM is actually increasing among indoor workers who receive three to nine times less solar UV radiation than outdoor workers. Furthermore, there is a higher incidence of CMM among whites living in northern states such Delaware, Vermont, and New Hampshire (>30 per 100,000), which enjoy less year-round sunlight and UV radiation than southern states such as Texas, Florida, Arizona, and New Mexico (

http://m.jabfm.org/content/24/6/735.full

Re: The Big Vitamin D Mistake

#440

Post by [deleted] »

hollander wrote: post #429
blurbleblurble wrote: post #251

Earlier quoted context omitted.

I recommend 1000 IU drops. They contain 1000 IU in a single drop, literally. You can get them off the shelf at my local health foods co-op. I've taken 40,000 IU before in a single day (I read that was a safe upper limit for most people). It felt amazing. It also helped me process built up emotions from winter darkness and depression. That day I took 40000IU I literally wept, then felt relief like none other, and a li…

Be careful with that kind of dose! To compensate for insufficiency, it's totally OK, but I wouldn't take it daily. You may start suffering from calcification of the bones. This cannot be undone.

[deleted]
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