The effect of ultraviolet radiation from a novel portable fluorescent lamp on serum 25-hydroxyvitamin D3 levels in healthy adults with Fitzpatrick skin types II and III.

BACKGROUND/PURPOSE Ultraviolet (UV) B irradiation may provide a safe and effective method to treat vitamin D deficiency. The objective of this study was to assess the effectiveness of a novel Sperti D/UV-Fluorescent lamp in converting 7-dehydrocholesterol (7-DHC) to previtamin D(3) in vitro and in raising serum 25-hydroxyvitamin D(3) [25(OH)D(3) ] in healthy adults. METHODS The lamp was assessed in vitro using a 7-DHC solution and a human skin sample. In a prospective cohort study, five healthy adults with skin types II and III were exposed to a 0.75 minimal erythemal dose of UV radiation over ≈ 9% of body surface area three times a week for 4 weeks. The main outcomes were percentage of conversion from 7-DHC to previtamin D(3) in vitro and changes in serum 25(OH)D(3) after irradiation in vivo. RESULTS A dose response between UV irradiation time and conversion of 7-DHC to previtamin D(3) was seen in the 7-DHC solution and surgically obtained human skin. The subjects had a significant increase in mean 25(OH)D(3) from 18.4 ± 8.2 to 27.3 ± 7.6 ng/ml (P < 0.001) after 4 weeks of irradiation. No adverse events occurred. CONCLUSION The Sperti D/UV-Fluorescent lamp is effective in converting 7-DHC to previtamin D(3) in vitro and in raising serum 25(OH)D(3) in healthy adults.