The burgeoning interest and expertise among both basic scientists and clinicians in the field of vitamin D metabolism, its endocrine system, and related diseases were evident at the Fifth Workshop on Vitaman D, held 14-19 February 1982, in Williamsburg, Virginia, and attended by over 450 delegates from 24 countries.
It is now accepted that circulating vitamin D, as dietary ergocalciferol (D2) or cutaneously photosynthesized cholecalciferol (D3), is hydroxylated in successive steps in the liver and kidney (25- and 1α-hydroxylation, respectively) to its more potent metabolites, 25 hydroxy vitamin D (25(OH)D) and 1,25 dihydroxyvitamin D (1,25(OH)2D), before it exerts its physiologic