Overall , intervention groups obtained higher 25(OH)D concentration than controls and there was obvious dose – response effect between intake dose and 25(OH)D concentration .
Baseline 25(OH)D concentration and age were significant indicators for 25(OH)D concentration .
Conclusions Regional- and age-specific recommended dosages of VitD supplements for population to achieve optimal 25(OH)D concentrations have been suggested
Background / Objectives Optimal doses of vitamin D ( VitD ) supplement in different population s are unclear .
We aim to evaluate the relationship between VitD supplementation and post-intervention serum 25-hydroxyvitamin D [ 25(OH)D ] concentration , to provide a recommended dosage of VitD for achieving an optimal 25(OH)D concentration for different population s .
Dose response to vitamin D supplementation in African Americans: results of a 4-arm, randomized, placebo-controlled trial.
BACKGROUND Association studies have suggested that lower circulating 25-hydroxyvitamin D [ 25(OH)D ] in African Americans may partially underlie higher rates of cardiovascular disease and cancer in this population . Nonetheless , the relation between vitamin D supplementation and 25(OH)D concentrations in African Americans remains undefined . OBJECTIVE Our primary objective was to determine the dose-response relation between vitamin D and plasma 25(OH)D. DESIGN A total of 328 African Americans in Boston , MA , were enrolled over 3 winters from 2007 to 2010 and r and omly assigned to receive a placebo or 1000 , 2000 , or 4000 IU vitamin D₃/d for 3 mo . Subjects completed sociodemographic and dietary question naires , and plasma sample s were drawn at baseline and 3 and 6 mo . RESULTS Median plasma 25(OH)D concentrations at baseline were 15.1 , 16.2 , 13.9 , and 15.7 ng/mL for subjects r and omly assigned to receive the placebo or 1000 , 2000 , or 4000 IU/d , respectively ( P = 0.63 ) . The median plasma 25(OH)D concentration at 3 mo differed significantly between supplementation arms at 13.7 , 29.7 , 34.8 , and 45.9 ng/mL , respectively ( P < 0.001 ) . An estimated 1640 IU vitamin D₃/d was needed to raise the plasma 25(OH)D concentration to ≥ 20 ng/mL in ≥ 97.5 % of participants , whereas a dose of 4000 IU/d was needed to achieve concentrations ≥ 33 ng/mL in ≥ 80 % of subjects . No significant hypercalcemia was seen in a subset of participants . CONCLUSIONS Within African Americans , an estimated 1640 IU vitamin D₃/d was required to achieve concentrations of plasma 25(OH)D recommended by the Institute of Medicine , whereas 4000 IU/d was needed to reach concentrations predicted to reduce cancer and cardiovascular disease risk in prospect i ve observational studies . These results may be helpful for informing future trials of disease prevention
Overall , intervention groups obtained higher 25(OH)D concentration than controls and there was obvious dose – response effect between intake dose and 25(OH)D concentration .
Baseline 25(OH)D concentration and age were significant indicators for 25(OH)D concentration .
Conclusions Regional- and age-specific recommended dosages of VitD supplements for population to achieve optimal 25(OH)D concentrations have been suggested
Background / Objectives Optimal doses of vitamin D ( VitD ) supplement in different population s are unclear .
We aim to evaluate the relationship between VitD supplementation and post-intervention serum 25-hydroxyvitamin D [ 25(OH)D ] concentration , to provide a recommended dosage of VitD for achieving an optimal 25(OH)D concentration for different population s .