Is tanning ever good for you? (Vitiligo)

Vitiligo is believed to be an autoimmune depigmentation disorder. The exact cause is unknown, but it is believed that the body's immune system attacks its melanocutes (pigment-producing cells). Our country's most popular vitiligo patient is probably Michael Jackson.

Light therapy is thought to have a dual mechanism of action on vitiligo. First its anti-inflammatory effects reduce the destruction of melanocytes. Second the UV stimulation activates the remaining melanocytes. Pigment is more likely to persist in hair follicles, which is why repigmentation occurs around them.

Yones SS et al. Randomized double-blind trial of treatment of vitiligo: Efficacy of psoralen–UV-A therapy vs narrowband–UV-B therapy. Arch Dermatol 2007 May; 143:578-84.

This study was really well done and presents good evidence that narrowband UVB is more effective in vitiligo treatment. Although the data was not quite statistically significant (p=0.06 instead of p<0.05) between the two groups, there was some difference. Any study on vitiligo therapy will be inherently flawed because of the subjective nature in judging repigmentation, but the methods included examination under Wood's lamp, comparison of nonlesional skin and repigmented skin color, patient survey, and a quality of life index. The amazing thing is that all 50 patients showed improvement. Although the Nb-UVB patients had better color match, fewer side effects, and more repigmentation.

Controlled UV exposure is a proven treatment for vitiligo.