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Jane Brody has a piece in today’s New York Times on vitamin D needs — nothing particularly new, but summing up the trend of the last few years to believe that insufficient vitamin D in modern sun-phobic societies is behind a whole range of chronic diseases, and noting that current recommended intakes are far below the levels some experts believe are necessary:
The current recommended intake of vitamin D, established by the Institute of Medicine, is 200 I.U. a day from birth to age 50 (including pregnant women); 400 for adults aged 50 to 70; and 600 for those older than 70. While a revision upward of these amounts is in the works, most experts expect it will err on the low side. Dr. Holick, among others, recommends a daily supplement of 1,000 to 2,000 units for all sun-deprived individuals, pregnant and lactating women, and adults older than 50.
With that in mind, it’s worth pointing out the press release from Osteoporosis Canada that I noticed last week, announcing a revision of their recommended vitamin D intake:
The new guidelines recommend daily supplements of 400 to 1000 IU for adults under age 50 without osteoporosis or conditions affecting vitamin D absorption. For adults over 50, supplements of between 800 and 2000 IU are recommended. For people who need added supplementation to reach optimal vitamin D levels, doses up to the current “tolerable upper intake level” (2000 IU) are safely taken without medical supervision.
I’m still a little gun-shy about the very broad claims made by vitamin D advocates, but the evidence is strong enough that D is the only supplement I’ve taken (albeit sporadically) over the past few years. The bottle I have right now is 400 IU per pill — maybe I need to ramp that up, or at least take it every day during the winter.