Licht-im-Terrarium: Literaturdatenbank
Licht-im-Terrarium: Literaturdatenbank |
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Vieth, R. (2006). What is the optimal vitamin d status for health? Progress in Biophysics and Molecular Biology, 92(1), 26–32. Added by: Sarina (2010-01-08 21:47:29) |
| Resource type: Journal Article BibTeX citation key: Vieth2006 View all bibliographic details  |
Categories: Englisch = English Keywords: Ultraviolett = Ultraviolet, Vitamin D = Vitamin D Creators: Vieth Collection: Progress in Biophysics and Molecular Biology |
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| Abstract |
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The most objectively substantiated health-related reason for tanning is that it improves vitamin D status. The serum 25-hydroxyvitamin D concentration (25(OH)D) is the measure of vitamin D nutrition status. Human biology was probably optimized through natural selection for a sun-rich environment that maintained serum 25(OH)D higher than 100 nmol/L. These levels are now only prevalent in people who spend an above-average amount of time outdoors, with the sun high in the sky. The best-characterized criteria for vitamin D adequacy are based on randomized clinical trials that show fracture prevention and preservation of bone mineral density. Based upon these studies, 25(OH)D concentrations should exceed 75 nmol/L. This concentration is near the upper end of the 25(OH)D reference (“normal”) range for populations living in temperate climates, or for people who practice sun-avoidance, or who wear head coverings. Officially mandated nutrition guidelines restrict vitamin D intake from fortified food and supplements to less than 25 mcg/day, a dose objectively shown to raise serum 25(OH)D in adults by about 25 nmol/L. The combined effect of current nutrition guidelines and current sun-avoidance advice is to ensure that adults who follow these recommendations will have 25(OH)D concentrations lower than 75 nmol/L. Therefore, advice to avoid UVB light should be accompanied by encouragement to supplement
Added by: Sarina |