Do Tans Protect Against Sun Damage?

Individuals with darker skin (for example, those of African and Asian ancestry) are much less likely to sustain ultraviolet (UV) radiation–induced DNA damage than those with lighter skin (e.g., those of European ancestry), but whether tanning protects lighter skin against UV damage is unresolved.

To address this issue, investigators exposed small areas of the skin of seven volunteers to suberythemal doses of either UVA or UVB radiation. The two spectra were examined separately because of their different gene expression profiles and because tanning beds emit large amounts of UVA radiation. At the doses employed, both UVA and UVB light produced equivalent amounts of pigmentation. Whereas UVB radiation increased melanin content and melanocyte d…