Evaluation of a Ultraviolet B Light Emitting Diode (LED) for Producing Vitamin D₃ in Human Skin

Abstract

Aim: A commercially available light emitting diode (LED) that transmitted narrow band ultraviolet B (UVB) radiation was evaluated for its efficacy and efficiency to produce vitamin D₃ in human skin. Materials and Methods: Human skin samples were obtained from surgical procedures. The LED had peak emission wavelength of 295 nm. Skin samples were exposed to the UVB-LED for varying times and then were analyzed by high-pressure liquid chromatography (HPLC) to determine the vitamin D₃ content. Results: There was a statistically significant time- and dose-dependent increase in the percent of 7-dehydrocholesterol that was converted to vitamin D₃ in the skin type II samples; 1.3%±0.5, 2.3%±0.6 and 4.5%±1.67 after exposure to 0.75 (11.7 mJ/cm²), 1.5 (23.4 mJ/cm²) and 3 (46.8 mJ/cm²) minimal erythemal doses (MEDs), respectively. Conclusion: The UVB-LED was effective and efficient in generating vitamin D₃ in human skin, in vitro. The amount of vitamin D₃ production increased in a dose-dependent fashion with increased UVB energy. UVB-LEDs can be developed for devices that can efficiently produce vitamin D₃ in human skin.