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22:47 Vitamin D! I've been deficient. Turns out: If you live in San Francisco, most of the year it's impossible to get enough from the sun because of our high latitude. To remedy this I've...
Mathieu Lonjaret's profile photoKevin Gibbs's profile photoDaniel Erat's profile photoBrett Slatkin's profile photo
As long as you're not taking them daily ;).
I've decided to take daily doses of 6k after the first few weeks on 1x50k/week.
I do it for two reasons, first is fear of hypervitaminosis, that's something you don't want to have from vitamin D, and with 50k/week and sunlight it's not that unlikely.
With daily doses I can adjust my intake depending on how much sunlight I get.

Additionally, placebo effect, in addition, should increase with daily intake ;).
Being a biased human, I can't possibly tell if it really makes a difference ;).
I had a friend who lives in SF and also has a D deficiency. I've also recently been diagnosed myself. I've had lots of joint and muscle pain that they haven't been able to find a cause, the only thing off (besides being overweight) is my vitamin D level.
D-deficiency is not commonly diagnosed here in Germany. It's a bit awkward, especially considering the daily suggested intake is a mere 200IU.
I've had various issues I was able to mitigate/get rid of with increased supplementation.
I've started taking D(3) 2000 IU daily -- I do live in SF, but I have a commute to a sunnier party of the bay ;)
Same in Seattle :) 10000IU daily for 3 months, then check levels
I had it too. Turns out brown people are particularly prone to it for the same reason we're highly resistant to melanoma.
Seth Roberts has written a bunch on his blog about D3 supplementation improving sleep: . I haven't noticed a difference, myself.

There's a large difference of opinion about whether supplementation does any good. The lecturer in an endocrinology class that I took at Stanford is optimistic, but vitamin D is his current focus. David Agus, an oncologist who spoke at Google recently, is skeptical. So's my doctor, although he humored my requests to get my level checked (lowish except when I was trying to get a lot of sun last summer; supplementation over the winter didn't help much). There's at least one big study underway that may help in a few years.
+Daniel Erat I've read a couple of interesting studies regarding brain immunology and vitamin D, for example concerning multiple sclerosis.
+Brett Slatkin That was not exactly my point, it was not a comparison with Europe. I simply wouldn't call 37 deg, or even 45 deg for that matter (where I live) a high latitude, strictly speaking.
But I get now from your answer that you were probably speaking in terms of population distribution on the North American continent?
FWIW, my doctor diagnosed me with this as well, and I took some Vitamin D supplements for a while... but I haven't managed to stick with it. I wouldn't be surprised if more than half of the office workers in the Bay Area would be found to have a D deficiency if they were tested for it. Which isn't to say it isn't a "problem," but if it is, it's one I suspect nearly everyone has.
Also, what's the source for the claim that it's "impossible" to get enough in SF? I was able to go from around 25 ng/mL to 45 or so between spring and fall last year by spending 15 minutes outside shirtless without sunscreen on sunny days. The rule of thumb I've heard is, "are you taller than your shadow is long?" (i.e. sun above 45°). Clouds are a factor as well, of course. Today seemed okay. :-P
+Daniel Erat it was the RN who did my blood test. Maybe "impossible" is really just that it's impractical given my lifestyle. 15 minutes outside shirtless daily sounds like a great use of time though. B-) You sure it wasn't the vitamin-D fortification in Tecate?
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