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 .
Vitamin D supplementation during Antarctic winter.
BACKGROUND Persons with limited exposure to ultraviolet B light , including space travelers , may not receive enough vitamin D. Recent studies indicate that optimal serum 25-hydroxyvitamin D [ 25(OH)D ] should be > or = 80 nmol/L. OBJECTIVE This study was design ed to evaluate the effectiveness of 3 doses of vitamin D to raise and maintain 25(OH)D to a concentration > 80 nmol/L in persons with limited ultraviolet B light exposure . DESIGN This was a 5-mo , prospect i ve , r and omized , double-blind study of vitamin D supplementation . It was conducted during winter in Anta rct ica at the McMurdo Station , when ultraviolet B radiation levels are essentially zero . The 55 subjects were r and omly divided into 3 groups for vitamin D supplementation : 2000 IU/d ( n = 18 ) , 1000 IU/d ( n = 19 ) , and 400 IU/d ( n = 18 ) . An additional 7 subjects did not take supplements or took supplements of their own choosing . Blood sample s were collected about every 2 mo during the winter . RESULTS About 5 mo after supplementation started , 25(OH)D increased to 71 + /- 23 nmol/L in the 2000-IU/d group , 63 + /- 25 nmol/L in the 1000-IU/d group , and 57 + /- 15 nmol/L in the 400-IU/d group and decreased to 34 + /- 12 nmol/L in the group not taking supplements . CONCLUSIONS These data will enable us to provide space crews with evidence -based recommendations for vitamin D supplementation . The findings also have implication s for other persons with limited ultraviolet light exposure , including polar workers and the elderly
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 .