@article {309992,
	title = {Increased skin pigment reduces the capacity of skin to synthesise vitamin D3.},
	journal = {Lancet},
	volume = {1},
	year = {1982},
	month = {1982 Jan 9},
	pages = {74-6},
	abstract = {<p>To determine the effect of increased skin pigment on the cutaneous production of vitamin D3, circulating vitamin D concentrations were determined in two lightly pigmented Caucasian and three heavily pigmented Negro volunteers after exposure to a single standard dose of ultraviolet radiation (UVR). Exposure of Caucasian subjects to 1 minimal erythemal dose of UVR greatly increased serum vitamin-D concentrations by up to 60-fold 24-48 h after exposure, whereas this dose did not significantly change serum vitamin-D concentrations in Negro subjects. Re-exposure of one Negro subject to a dose of UVR six times larger than the standard dose increased circulating vitamin D to concentrations similar to those recorded in Caucasian subjects after exposure to the lower dose. These results indicate that increased skin pigment can greatly reduce the UVR-mediated synthesis of vitamin D.</p>
},
	keywords = {African Continental Ancestry Group, Cholecalciferol, European Continental Ancestry Group, Humans, Melanins, Radiation Dosage, Rickets, Skin, Skin Pigmentation, Ultraviolet Rays, Ultraviolet Therapy, vitamin D},
	issn = {0140-6736},
	author = {Clemens, T L and Adams, J S and Henderson, S L and Holick, M F}
}
