As mentioned, as you get older your skin doesn't make as much vitamin D in response to sun exposure. (articles.mercola.com)
Overweight / obese blacks are at increased risk for vitamin D deficiency because darker skin absorbs less sunlight — the skin makes vitamin D in response to sun exposure — and fat tends to sequester vitamin D for no apparent purpose, says Dong, the study's corresponding author. (sciencedaily.com)
Overweight blacks are at increased risk for vitamin D deficiency because darker skin absorbs less sunlight — the skin makes vitamin D in response to sun exposure — and fat tends to sequester vitamin D for no apparent purpose. (sciencedaily.com)