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The Big Vitamin D Mistake

ncbi.nlm.nih.gov

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Re: The Big Vitamin D Mistake

#61

Post by ianai »

bbunix wrote: post #31
rapsey wrote: post #19

Earlier quoted context omitted.

The amount of disinformation commonly expressed about vitamin D is quite amazing. Bogus claims: 1. Spend a couple of minutes outside and you will be OK. 2. It is absorbed through the eyes. 3. Deficiencies are rare. When in fact: 1. Does not apply at any time when your body is covered up mostly. Wear trousers and a T-shirt and you've cut yourself off severely already. Add weather with less sun, sunscreen, and/or more…

You'd think sunny places would fare better - however after moving to Key West from Montreal I discovered people here spent a lot of effort avoiding the sun (skin cancer is big down here).

As someone with fair skin, I’d be harming myself if I tried to get vitamin D from the sun. And very badly.

Re: The Big Vitamin D Mistake

#62

Post by theprotocol »

timewarrior wrote: post #52

One point of caution: Anyone who takes Vitamin D supplement, make sure you take 25-Hydroxy (Calcifediol) and not the active form - 1,25 dihydroxy (Calcitriol). Active form has severe side effects and is not supposed to be used for supplementation unless in you have kidney problem which prevent metabolizing 25-Hydroxy.

I thought all D2 and D3 supplements would be ergocalciferol and cholecalciferol, respectively, while calcitriol is what gets tested to assess blood levels. Do any supplements actually contain calcitriol?

Re: The Big Vitamin D Mistake

#63

Post by trhway »

not to mention apparent connection to autism. Best example - Somali immigrant populations concentrated in Sweden and Minnesota have unnaturally high child autism rates and extremely low vitamin D levels (very dark skin, weak Sun, a lot of clothes covering almost the whole body most of the year due to the cold climate). Another Swedish study found, though much smaller effect, uptick in autism rates among children whose 3rd trimester, when the brain develops the fastest, fell onto the winter.

Re: The Big Vitamin D Mistake

#64

Post by Gibbon1 »

pkaye wrote: post #36
timewarrior wrote: post #30

Earlier quoted context omitted.

Another big challenge in winter months is that people are so covered with warm clothes, that even going out in Sun doesn't help much.

I wonder if glass windows would block out the benefits?

Ordinary window glass blocks 90% of UV-B which is needed to produce VitD.

I do remember reading years ago about a sanitarium in the late 1800's - early 1900 where the windows in the sun rooms were quartz glass.

Re: The Big Vitamin D Mistake

#65

Post by tpowell »

arca_vorago wrote: post #29
timewarrior wrote: post #14

This article recommends around 100 nmol/L. Most people are between 20-30, because they don't get enough Sun and do not take supplements. It gets really really bad when the number gets below 10 and it takes months to recover. Another Vitamin whose deficiency cause irreversible damage is B12. Folks, get both of these checked.

I just want to say the b complexes are indeed super important, but recent studies indicate a potential link between overly high dosage and some types of cancers, particularly in men. So be wary of overdoing it with those 3000% dv supplements.

I threw out some vitamins and energy drinks after reading about this.

https://www.theatlantic.com/health/archive/2017/08/b12-energ...

Re: The Big Vitamin D Mistake

#66

Post by basicplus2 »

tathougies wrote: post #28
basicplus2 wrote: post #16

Sufficient vitamin D is gained primarily from Sun exposure.. typically between 10am and 2pm, I have read that at certain latitudes and times of year the required window is considerably less but cannot find a reference. http://www.return2health.net/articles/does-vitamin-d-really-...

This is a very caucasian centric viewpoint. The fact is that if you live in higher latitudes and have dark skin, you physically cannot absorb enough vitamin D from sunlight during the winter months. While it is physically possible during the summer, it is not practical to spend hours sunbathing.

That's a very coloured centric viewpoint.

The fact is that the majority of people of planet earth can go out in the sunshine at the right time of day and get 80-90% the vitamin D they need and get the rest from a balanced diet.

Re: The Big Vitamin D Mistake

#68

Post by theprotocol »

If the recommendations of this study become the guideline, it may validate the other studies suggesting that nearly everyone is deficient in magnesium, which is a co-factor in the Vitamin D / calcium cycle.

AFAIK (and correct me if I'm wrong), the vitamin D metabolism requires magnesium, calcium, vitamin K2, and vitamin A. K2 in particular needs special attention, as it's the hardest of the substrates to get.

Re: The Big Vitamin D Mistake

#69

Post by darshan »

noahdesu wrote: post #45

Has anyone had experience ordering blood work (e.g. the vitamin d 25 hydroxy test) without visiting a doctor? I've seen very few references to the set of sites that pop up first online [0, 1, 2, 3] when I've gone looking for reviews in the past. Any suggestions? I'm in CA. [0]: https://www.privatemdlabs.com [1]: http://www.directlabs.com/ [2]: https://www.walkinlab.com/ [3]: https://www.health-tests-direct.com/

I've used Direct Labs multiple times over the years (including for 25 hydroxy) and I've always been perfectly happy with them.

Re: The Big Vitamin D Mistake

#70

Post by theprotocol »

DigitalJack wrote: post #20
timewarrior wrote: post #14

This article recommends around 100 nmol/L. Most people are between 20-30, because they don't get enough Sun and do not take supplements. It gets really really bad when the number gets below 10 and it takes months to recover. Another Vitamin whose deficiency cause irreversible damage is B12. Folks, get both of these checked.

I happen to have a gene mutation that makes methylation of B12 inefficient. I never did well in chemistry or biology for that matter, but my limited understanding is that methylation is necessary for it to be useful. It turns out that you can buy methylated B12 called methylcobalamin. The more common form is cyanocobalamin, and is not very useful for people like myself. That is my understanding, if anyone here knows…

Does the typical B12 blood test test for this? Or do you have normal levels even without supplementing methylcobalamin?
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