Ultraviolet (UV)-B light increases vitamin D levels, but the dose response and the effect of skin pigmentation have not been well characterized.
We sought to define the relationship between UVB exposure and 25-hydroxyvitamin D (25-OH-D) concentrations as a function of skin pigmentation.
Seventy two participants with various skin tones had 90% of their skin exposed to UVB light (20-80 mJ/cm2) 3 times a week for 4 weeks. Serum 25-OH-D was measured weekly.
Eighty percent of the variation in treatment response was explained by UVB dose and skin tone. Therapeutically important changes in 25-OH-D were achieved with minimal tanning.
Four weeks was not long enough to reach a steady state at the higher dose rates.
The response of 25-OH-D levels to UVB light is dependent on skin pigmentation and the amount of UVB given, and useful increases in vitamin D status can be achieved by defined UVB doses small enough to produce only minimal tanning.Le texte complet de cet article est disponible en PDF.
Abbreviations used : L, 25-OH-D, PTH, UV
| Supported by Dialysis Clinics Inc, The Endocrine Fellows Foundation, and research funds of Creighton University.
| Disclosure: Dr Hollis is a consultant for Diasorin. Diasorin manufactures assays for 25-hydroxyvitamin D. Drs Armas, Dowell, Akhter, Duthuluru, Huerter, Lund, and Heaney have no conflicts of interest to declare.
| Reprints not available from the authors.