Bone Abstracts

There is wide variation in the dose-response to oral vitamin D and the increment in plasma 25(OH)D decreases per unit vitamin D given. We hypothesised that this is related to increased 25(OH)D catabolism as reflected in 25OHD half-life (25(OH)D3 t1/2).Design: 25(OH)D3 t1/2 was measured with a stable isotope (SI) technique in older (70y+) men and women in the UK during winter before (<...

Low circulating levels of total 25-hydroxyvitamin D (25OHD) have been reported in obese people of different ethnicities in several countries. Low total 25OHD in obesity could be due to lower binding proteins (with normal free 25OHD), lower dietary intake or sunlight exposure, greater volume of distribution (pool size) or more rapid metabolic clearance.The aims of this study were to determine if free 25OHD and 1,25-dihydroxyvitamin D (1,25(OH)2...