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 D3 supplementation during weight loss: a double-blind randomized controlled trial.
BACKGROUND Vitamin D deficiency is associated with obesity ; whether repletion supports weight loss and changes obesity-related biomarkers is unknown . OBJECTIVE We compared 12 mo of vitamin D3 supplementation with placebo  on weight , body composition , insulin , and C-reactive protein ( CRP ) in postmenopausal women in a weight-loss intervention . DESIGN A total of 218 overweight/obese women ( 50 - 75 y of age ) with serum 25-hydroxyvitamin D [ 25(OH)D ] ≥10 ng/mL but < 32 ng/mL were r and omly assigned to weight loss + 2000 IU oral vitamin D3/d or weight loss + daily placebo . The weight-loss intervention included a reduced-calorie diet ( 10 % weight loss goal ) and 225 min/wk of moderate-to-vigorous aerobic activity . Mean 12-mo changes in weight , body composition , serum insulin , CRP , and 25(OH)D were compared between groups ( intent-to-treat ) by using generalized estimating equations . RESULTS A total of 86 % of participants completed the 12-mo measurements . The mean ( 95 % CI ) change in 25(OH)D was 13.6 ( 11.6 , 15.4 ) ng/mL in the vitamin D3 arm compared with -1.3 ( -2.6 , -0.3 ) ng/mL in the placebo arm ( P < 0.0001 ) . Changes in weight [ -7.1 ( -8.7 , -5.7 ) compared with -7.4 ( -8.1 , -5.4 ) kg ] , body mass index ( in kg/m(2 ) : both -2.8 ) , waist circumference [ -4.9 ( -6.7 , -2.9 ) compared with -4.5 ( -5.6 , -2.6 ) cm ] , percentage body fat [ -4.1 ( -4.9 , -2.9 ) compared with -3.5 ( -4.5 , -2.5 ) ] , trunk fat [ -4.1 ( -4.7 , -3.0 ) compared with -3.7 ( -4.3 , -2.9 ) kg ] , insulin [ -2.5 ( -3.4 , -1.7 ) compared with -2.4 ( -3.3 , -1.4 ) μU/mL ] , and CRP [ -0.9 ( -1.2 , -0.6 ) compared with -0.79 ( -0.9 , -0.4 ) mg/L ] [ corrected ] were similar between groups ( all P > 0.05 ) . Compared with women who achieved 25(OH)D < 32 ng/mL , women r and omly assigned to vitamin D who became replete ( ie , 25(OH)D ≥32 ng/mL ) lost more weight [ -8.8 ( -11.1 , -6.9 ) compared with -5.6 ( -7.2 , -5.0 ) kg ; P = 0.05 ] , waist circumference [ -6.6 ( -9.3 , -4.3 ) compared with -2.5 ( -4.6 , -2.0 ) cm ; P = 0.02 ] , and percentage body fat [ -4.7 ( -6.1 , -3.5 ) compared with -2.6 ( -3.9 , -2.2 ) ; P = 0.04 ] . Among women with complete pill counts ( 97 % adherence ) , the mean decrease in CRP was 1.18 mg/mL ( 46 % ) in the vitamin D arm compared with 0.46 mg/mL ( 25 % ) in the placebo arm ( P = 0.03 ) . CONCLUSIONS Vitamin D3 supplementation  during weight loss did not increase weight loss or associated factors compared with placebo ; however , women who became replete experienced greater improvements . This trial was registered at clinical trials.gov as NCT01240213
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 .