The DV for Vitamin D is 400iu, the RDA is 600iu. I know many experts have been recommending at least 4000iu, however this article claims it should be 7000iu. Aside from fortified items such as milk or orange juice, which typically have 25% of DV (100iu), and relatively small amounts in mushrooms, we cannot realistically obtain adequate levels vitamin d from our diet. Another option is exposure to sunlight, particularily the UVB wavelengths. Your body can produce plenty of vitamin D with relatively low exposure. Some people fear the DNA damaging UV light and wear sunscreen which blocks the harmful light but also the UVB light that stimulates vitamin D production. Other considerations regarding sun exposure are your geographic location, skin complexion, seasons and the sun angle/time of day. Further from the equator, less production occurs, the darker your skin, the less production, late fall through early spring in most of America you will get no vitamin d production from sun exposure, lastly, the further the sun from directly above, the less production. Aside from those, you can supplement vitamin D. Most experts seem to agree vitamin d3 is the best form, and the best part, its really cheap and very beneficial for your overall health. Oh, here is the link! http://www.sciencedaily.com/releases/2015/03/150317122458.htm
I saw this article, and thought, "Rhonda Patrick was right!" http://www.hsph.harvard.edu/nutritionsource/vitamin-d/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2726624/ http://www.ncbi.nlm.nih.gov/pubmed/17372031/ http://www.ncbi.nlm.nih.gov/pubmed/18003755/ http://www.ncbi.nlm.nih.gov/pubmed/18793245/ http://www.ncbi.nlm.nih.gov/pubmed/17277040/ http://www.ncbi.nlm.nih.gov/pubmed/17179460/ http://www.ncbi.nlm.nih.gov/pubmed/11705562/ A few links on vitamin D, deficiency of it, and its health effects.
Your first link reminded me, i should add extra body fat also reduces blood levels of vitamin D because it is fat soluble and is absorbed into your fat tissue (thus not in your blood doing what it need to do). Though if you get plenty of sun and put on some fat for winter, maybe as oue body burns the fat it will sustain you until next spring?
the best source of vitamin d is the sun. fatty fish, mushrooms, cod liver oil... and maybe then synthetic vitamins. i would say that in general recommended dosages for vitamins are almost always too low. and whenever you take a supplement you really need consider its bioavailability. http://smartypantsvitamins.com/bioavailability/ not to say that supplements aren't necessary, but the very first goal should be to seek natural sources. also before going on a quest for more vitamin d, it's probably a good idea to get a simple blood test done to understand if/how deficient you are in reality.
Good advice. I think 10,000 i.u per day is the upper limit. One thing for people to remember, if you are getting lots of vitamin d, you will also need to increase your magnesium intake, which most people are already deficient in anyway. Solution? Eat nuts and seeds!
Thanks for the info. Even though I live in southern california I work graveyard shift so I probably don't get enough sun. I'm weary of taking too many vitamins but I recently started taking one a day multivitamin. It contains 700iu Vitamin D but maybe I need to add more.
most multi vitamins are useless.. .you can't pack anything worthwhile into a single pill, if you want to add all sorts of vitamins and minerals in reasonable dosages. that would be one gigantic pill. if anything try to find a liquid multi vitamin (vegetable/fruit based and organic). otherwise it's best to stick to specific supplements if you really need them. http://examine.com/faq/do-i-need-a-multivitamin
Not all things works for everyone, similarly some people may need heavy dose and some light. So there is not a fixed principle in this matter. I mostly try to get mine from natural resources.
Check this out... its the best product i could find for a broad spectrum aid to health. Ita called Green Vibrance... i enjoy the taste when added to real orange juice.
I take 3000iu per day. I live pretty damn far north and we have long dark winters. I should probaby bump mine up to 4,000 or more. Due for more bloodwork anyways.