Gene Expression

Are you getting enough vitamin D?:

The research, which is awaiting publication in a medical journal, found that 100 per cent of those of African origin were short of vitamin D, as were 93 per cent of South Asians (those of Indian or Pakistani origin), and 85 per cent of East Asians (those of Chinese, Indochinese or Filipino origin, among other countries).

Insufficient vitamin D amounts were also found among those of European ancestry, but were less widespread, at 34 per cent of those surveyed.

This is in Canada, very far north. That being said, if 93 percent of South Asians in Canada have Vitamin D deficiency I doubt it is that much lower in the United States, we aren’t that far south. Additionally, a greater proportion of Canadian South Asians are light skinned Punjabis, while more American South Asians are darker skinned Gujaratis. My doctor had me tested because she knew I didn’t drink milk, and her own olive skin had resulted in her having a deficiency. As for as other groups, blacks and East Asians are generally not lactose tolerant, so it is more likely that these groups won’t be drinking fortified milk. That’s a problem.

Why should you care? There are probably some long term consequences in terms of chronic diseases of old age, but the biggest issue is probably it makes you more susceptible to flu and other low grade ailments. It’s a quality of life issue.


  1. #1 Edward Hutchinson
    December 23, 2007

    Not enough vitamin D Health consequences for Canadians is the title of a Clinical Review by Gerry Schwalfenberg, MD in the May edition of Canadian Family Physician. The full text is available online and is interesting reading if you want to understand the extent of vitamin D insufficiency.

    It really isn’t just brown skinned Canadians at risk of Vit D insufficiency, though darker skin makes vitamin d3 photosynthesis slower.

    Researchers have estimated that the oral dose of vitamin D3 to attain and maintain 25(OH)D levels >80 nmol/L is 2200 IU/d if baseline levels are 20 to 40 nmol/L, 1800 IU/d if levels are 40 to 60 nmol/L, and 1160 IU/d if levels are between 60 and 80 nmol/L

    80nmol/l is the level that enables maximum uptake of calcium from diet and achieves a 72% lower incidence of colon cancer.

    130nmol/l achieves optimum feelings of well being, peak muscle performance and lowest overall cancer incidence. 18 cancers have lower incidence at higher vitamin D status.

    The amounts of vitamin D available in fortified milk vary considerably and are generally less than stated. As no one can drink 40 glasses of milk daily or consume ten portions of oily fish, in practice, it is only possible to obtain 10% of daily vitamin D requirement from diet, the rest must come from UVB sources or D3 Cholecalciferol supplements.

  2. #2 Macnerdzcare
    December 23, 2007

    i never thought that vitamin-D difficieny is that rampant. i thought everyone is getting enough of it since the skin produces vitamin-d when exposed to sunlight

  3. #3 razib
    December 23, 2007

    i thought everyone is getting enough of it since the skin produces vitamin-d when exposed to sunlight

    brown skinned people produce at 1/6th the rate of white skinned people.

  4. #4 chris
    December 23, 2007

    Interesting, I take a multivitamin that has 400 IU of Vitamin D. (Are there different types of Vitamin D?). Sounds like that wouldn’t make a difference.

    I’m also surprised about the East Asians. I didn’t think their skin was that dark that it would interfere. I’ve known South Asians with very, very dark skin, on the other hand.

    On a purely visual level I’ve now many southern Europeans (ie Italians) with darker skin than most East Asians I’ve known.

    On a different note I know an Indian couple and the guy often teases his wife by calling her a Guji (I assume that means from Gujarat). But neither of them are from there (they are from somewhere more to the south.)

    I haven’t been able to pick up the exact meaning. She’ll do something he disapproves of and he’ll say, don’t be such a Guji, or something like that, but in a playful, teasing manner. At first I thought it meant being air-headed, and then I thought it meant being cheap. Any ideas?

  5. #5 Megan
    December 23, 2007

    As a lot of blacks live in the south in the U.S. I would think American blacks would have more vitamin D than blacks in Canada. The mid-Atlantic, South, Southwest and West really are pretty sunny.

  6. #6 Phy
    December 24, 2007

    The study was done in Toronto, which is as far south as Boise, Rapid City, or Portland, ME.

  7. #7 David B
    December 24, 2007

    Vitamin D deficiency has been reported among South Asians in Britain, as a consequence of insufficient sunlight and eating only food (ghee, etc) from Asian stores, which is not reinforced with vitamins. Some foods in Britain are routinely reinforced with vitamin D to prevent rickets, which was common in drak industrial towns in the bad old days.

  8. #8 ogunsiron
    December 27, 2007

    I was pretty surprised by this.
    I had assumed that pretty much everyone got more or less enough vitamin D because of our modern dairy rich diet . I guess it’s time to start taking supplements .

  9. #9 arthtritis
    June 27, 2008

    milk on the grocery stores have been Vitamin-D fortified already.

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