Monday, April 02, 2007
So why are white people white? And let’s skip the ”because God wanted it that way” answer. We know that humankind, of the homo sapient version, started out dark-skinned around the horn of Africa, at least 6,000 years ago. We also know that white skin was not a random mutation, but rather an adaptive genetic response to less available ultra-violet (UV) laced sunlight, as Africans ventured farther north into Eurasia.
But again, why white? Skin-cancer mortality occurs after reproduction, so this influence is negligible. In part, it turns out that as the body’s essential vitamin D production decreased, from less sunlight as we moved north, a host of health problems followed, ultimately including reproductive interruption. Light-skin absorbs more sunlight, thereby inducing the production of vitamin D in reduced light and reversing the loss. Overtime, and for this reason, melanin levels in people’s skin closely matches the latitude of their ancestors.
Researchers are beginning to match-up our current health data against the adaptive responses that have occurred over time, with some rather startling revelations. This matching is necessary, given the abrupt movement of dark-skinned people to higher latitudes, as occurred during the Atlantic slave trade. It turns out that a disproportion of the disparities we see in health between blacks and whites is the logical outcome of this abrupt movement.
Vitamin D’s influence on our bodies is far greater than science has previously understood. The occurrence of many cancers seems to correlate directly to sun exposure and Vitamin D levels, as D is believed to regulate cell growth. Breast, colon, and prostate cancer prevalent in blacks, as well as autoimmune, diabetes and heart disease, correlate to vitamin D deficiencies, and also show up in whites in the higher latitudes, such as Scandinavia, as we would expect.
Researchers at the Centers for Disease Control and Prevention (CDC) report that 42 percent of African American women of childbearing age are Vitamin D deficient. In places like Boston and Seattle in the winter, D production drops to zero for whites, and the same for blacks living even farther south than places like San Francisco, Denver, Philadelphia, and Columbus.
Currently the FDA recommends that people (presumably white) under the age of 50, get 200 IUs a day; 51- to 60- year-olds take 400 IUs; and over 70 get 600 IUs. These numbers are likely to be revised significantly higher, and even higher still for dark-skinned people. What is clear is that everyone, especially blacks, should, at the least, be taking the daily requirement for the protection of this essential and affordable vitamin.
Vitamin D, take it to live!
James C. Collier
READ MORE ACTING WHITE...
Technorati Tags: Acting White: Vitamin D Gap in Black & White, Disparity, Black Health, Sunscreen, Cancer, Acting White