CIE 174:2006 Action spectrum for the production of previtamin D3 in human skin

Ultraviolet radiation has been shown to have the beneficial effect of contributing to the production of vitamin D3 (hereafter referred to as Vitamin D ) in humans. This was first observed in the 1800's, when sunlight exposure was correlated to the prevention of rickets. These effects were duplicated with artificial sources, and subsequent studies isolated the spectral region that was responsible for this effect. The purpose of this report is to discuss these studies of the effectiveness of optical radiation on the production of vitamin D in human skin, and to develop a standardized action spectrum for vitamin D synthesis in human skin. Implications for determining exposures that would be needed for an individual to meet the recommended daily intake for vitamin D are also discussed. Keywords: actinic action spectrum, actinic radiation effects, biologic effect of radiation, photobiology, ultraviolet radiation