Vit D: Not so sure supplementation is wise anymore... to a point.

[62shelby]

Ok, heres the thing. Recently, and I am sorry, I cant remember where I read it, but it was on a paleo docs blog, he was talking about the role vit d and the thyroid. It was along the lines that physiologically, in the summer, we receive abundance. Abundance of sunshine and abundance of food. that the sunshine and vit d, DOWN regulates the thyroid so we could store the abundance for the harsher seasons to come. Then when the winter months come the lack of sunshine triggers the thyroid to UP regulate to the burn the stored fuel. Then Nora Gedgaudas apparently mentioned in a recent post that she didnt think direct hormone replacement was a good idea, instead that the building blocks be provided in order to rebuild the hormones. Vit D is considered a hormone. The seasonal theory makes sense to me. Thoughts anyone?

[chadwick]

shelby: do you have any links you could provide to read about this? I am interested in learning more about it.

Are you saying lots of sunlight acts as hormone replacement? IMO, sunlight is the MOST natural method of getting Vitamin D, and of course there is some from food. But sunlight provides much more. Am I following correctly?

[62shelby]

Chadwick, I shall look for the blog entry that I read that discussed this, it may take me a while to dig it up and its on another laptop in another country right now, but, vit d, I have read is considered a hormone. I guess what I am thinking is, that I am not sure we are meant to have perpetually high levels of vit d, as seems fashionable of late, that yes, we are meant to get it from sunlight and not from supplements, and that it might need to be seasonal exposure, in order for our hormone cascade to work properly to protect us. Then I start thinking of the Inuit, and other arctic dwellers etc, they hardly get any sunlight in the winter months, yet they have coped for millenia havent they?

[pkafka]

shelby - interesting question! Thanks. Are you typically ant i- supplement? This makes sense to me - Cave people got Vitamin D from the sun (or in the summer and spring)... Thus there is a good chance that people might not need an excess of it (or supplement their diet with it) during the fall and winter.

A lot of people, including me, ask this same question in reference to fruit - should we only eat what is in season? If berries only grow in the fall, a lot of people believe that we should only eat them in the fall, and at no other points in the year... This makes sense to me. But to answer your question about Vit. D, I am going to need to read/think further.

Thanks for getting my wheels turning!

-pk

[fitnessphreak18]

I recently read that "People who are exposed to normal quantities of sunlight do not need vitamin D supplements because sunlight promotes sufficient vitamin D synthesis in the skin."

But, I guess a question to ask would be - what about people who live in areas with very little sunlight... and then I guess my answer to that would be - cave people didn't live in those areas... they could not have survived! is this right?

In conclusion, Vit. D supplements, in my opinion, are not needed if you live in a livable place.

[Tarlach]

Just get out in the sun:
http://nadir.nilu.no/~olaeng/fastrt/VitD-ez_quartMED.html

Supplements are not necessary.

The half life of vitamin D is 3-4 weeks. If you do get some sun when it is warm, then you should be able to go for quite a few months without any sun exposure at all.

Adequate amounts of vitamin D3 can be made in the skin after only ten to fifteen minutes of sun exposure at least two times per week to the face, arms, hands, or back without sunscreen.
http://en.wikipedia.org/wiki/Vitamin_D

[chadwick]

Concerning vitamin D, there was a good study recently released with respect to vitD & cancer.

Full study here: http://www.grassrootshealth.org/_download/Garland_C_Cance_%20Vitamin_%20DV1.pdf

Summary by Richard @ Free the Animal: http://freetheanimal.com/2008/12/vitamin-d-deficiency-and-all-cancer.html

[BMcD]

Hello. Just joined. I'm a little concerned about my D3 supplementation too. Living in NYC. Not a lot of sun right now and I work in an office building. So i'm supplementing, varying the amount usually between 1200 - 3000 mg a day. Occasionally skipping a day. Here's an interesting site with some anti D supplementation perspectives. <http://bacteriality.com/>

[chadwick]

Hello. Just joined. I'm a little concerned about my D3 supplementation too. Living in NYC. Not a lot of sun right now and I work in an office building. So i'm supplementing, varying the amount usually between 1200 - 3000 mg a day. Occasionally skipping a day. Here's an interesting site with some anti D supplementation perspectives. &lt;http://bacteriality.com/&gt;

I agree BMcD. I try to get out in the sun as well, but I admit I can and will do a better job of it!