Seborrheic dermatitis and daylight.

Patients with mood depression have been found to have a higher prevalence of seborrheic dermatitis (SD), possibly related to their tendency to live indoors. The prevalence of outpatients with SD has now been found to be directly related to the number of gloomy days in the area. Since UV light might not be the only reason for the well-known improvement in SD in summer, an explanation possibly related to melatonin is envisaged.