Recently I came across two interesting articles about Vitamin D deficiency in African-Americans, and the possible effects this widespread deficiency is having on the black community. Because of their dark skin, it takes blacks 2-5 times longer time in the sun to make Vitamin D than it takes white people. As a result, many African-Americans in the United States and Canada are Vitamin D deficient, especially black teens (black teens are 20 times more likely to be Vitamin D deficient than white teens). Dark skin is actually an adaptation to prolonged sun exposure, so Africans living in sub-Saharan Africa would make plenty of Vitamin D under normal conditions, but when living in northern areas, their skins have difficulty making the vitamin). Traditionally, peoples living far north, like the Inuits, have adapted by eating foods high in Vitamin D (in their traditional diets), but modern diets of people living in northern areas have very little Vitamin D.
Almost exactly two years ago, the blog Acting White posted about Vitamin D and Learning Disadvantages in Black Children. In it, the author (James Collier), argues that rampant Vitamin D deficiency among black mothers and black children is giving them a strong neuro-developmental disadvantage throughout life. As Collier points out, Vitamin D is cheap and beneficial for every race.
Another article I was reading, points out that blacks have lower cancer survival rates than whites, even at the same stage of cancer, and using the same treatment. Some researches have concluded that a Vitamin D deficiency is responsible for this disparity. In a study published in the journal of the AMA, it was found that summertime UV-B doses were inversely associated with incidences of major cancers in African-Americans, which means that the less UV-B rays a person was exposed to, the higher the rate of cancer. Again, according to the same article, a study found that blood levels of Calcidiol, equivalent to an intake of 1000 IU/day of Vitamin D, reduced the risk of colon cancer by 50%. While white Americans do not achieve this level, whites, on average, have 50 to 67% of the proper Calcidiol level. However, blacks, on average, only have 33 to 50% of the level.
Vitamin D deficiency is something that we all have to address, but it seems like African-Americans would benefit from exploring supplementation with Vitamin D, since blacks living in most of the U.S. and Canada have a disadvantage when it comes to making Vitamin D.