title: The effect of melanism and vitamin D synthesis on the incidence of autoimmune disease.
abstract: Melanin has several physiological roles in maintaining health, but, notably, it affects the synthesis of vitamin D. Melanin is the primary determinant of the degree of skin pigmentation and protects the body from harmful ultraviolet radiation. Synthesis of 1,25-dihydroxyvitamin D(3) (1,25[OH](2)D(3)) in the skin, however, is dependent on ultraviolet B light. Highly pigmented skin, to the level found in people of African origin, abrogates almost all ultraviolet-induced 1,25(OH)(2)D(3) synthesis. Numerous animal models and clinical studies have underlined the essential role of vitamin D as a modulator of the different processes of the immune system. Evidence indicates that serum concentrations of 1,25(OH)(2)D(3) and the prevalence of autoimmune diseases in a certain population are associated with the latitude at which that population resides. This article explores the relationship between skin pigmentation, vitamin D and the prevalence of autoimmune disease.
authors.affiliation: Be'er Ya'akov Mental Health Center, Be'er Ya'akov, Israel.
authors.forename: Netta
authors.initials: N
authors.lastname: Shoenfeld
authors.forename: Howard
authors.initials: H
authors.lastname: Amital
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Shoenfeld
mesh_terms: D000818:Animals; D001327:Autoimmune Diseases / Q000097:blood / Q000453:epidemiology*; D002117:Calcitriol / Q000096:biosynthesis* / Q000097:blood; D004195:Disease Models, Animal; D006801:Humans; D008543:Melanins / Q000378:metabolism*; D015995:Prevalence; D018167:Receptors, Calcitriol / Q000378:metabolism / Q000528:radiation effects; D012880:Skin Pigmentation / Q000502:physiology*; D014466:Ultraviolet Rays; D014808:Vitamin D Deficiency
chemical_list: D008543:Melanins; D018167:Receptors, Calcitriol; D002117:Calcitriol