Beneficial effects of UV radiation other than via vitamin D production
This is an open access article.
Volume 4, Issue 2 April/May 2012
Keywords: heliotherapy, nitric oxide, photoprotection, phototherapy, tanning, ultraviolet radiation, vitamin D synthesis
Authors: Asta Juzeniene and Johan Moan
Most of the positive effects of solar radiation are mediated via UV B (UVB) induced production of vitamin D in skin. However, several other pathways may exist for the action of UV (UV) radiation on humans as focused on in this review. One is induction of cosmetic tanning (immediate pigment darkening, persistent pigment darkening and delayed tanning). UVB-induced, delayed tanning (increases melanin in skin after several days), acts as a sunscreen. Several human skin diseases, like psoriasis, vitiligo, actopic dermatitis and localized scleroderma, can be treated with solar radiation (heliotherapy) or artificial UV radiation (phototherapy). UV exposure can suppress the clinical symptoms of multiple sclerosis independently of vitamin D synthesis. Furthermore, UV generates nitric oxide (NO), which may reduce blood pressure and generally improve cardiovascular health. UVA-induced NO may also have antimicrobial effects, and, furthermore, act as a neurotransmitter. Finally, UV exposure may improve mood through the release of endorphins.