CONCLUSIONS Supplementation with vitamin D showed no effect on adiposity measures in adults
CONTEXT The independent or interactive effects of vitamin D and calcium on adiposity remain inconclusive .
OBJECTIVE The objective of this systematic review and meta- analysis was to assess whether vitamin D and calcium supplements cause changes in adiposity .
High-Dose Vitamin D Supplementation in People With Prediabetes and Hypovitaminosis D
OBJECTIVE Low vitamin D levels predict the development of diabetes . This double-blind , r and omized , control study in subjects with prediabetes and hypovitaminosis D evaluated whether high doses of vitamin D for 1 year affected insulin secretion , insulin sensitivity , and the development of diabetes . RESEARCH DESIGN AND METHODS A total of 1,551 subjects ≥40 years of age not known to have diabetes were screened with A1C levels . Subjects with A1C levels of 5.8–6.9 % underwent an oral glucose tolerance test ( OGTT ) . Subjects with prediabetes and 25-OH vitamin D ( 25-OHD ) levels < 30 ng/mL were r and omized to receive weekly placebo ( n = 53 ) or vitamin D ( n = 56 ) with doses based on body weight and baseline 25-OHD levels . OGTTs were performed 3 , 6 , 9 , and 12 months later . Insulin secretion and sensitivity were measured , and the proportion of subjects developing diabetes was assessed . RESULTS 25-OHD levels rapidly rose from 22 to nearly 70 ng/mL after vitamin D supplementation with a mean weekly dose of 88,865 IU . There were no differences between the placebo and vitamin D groups regarding fasting plasma glucose , 2-h glucose , or insulin secretion and sensitivity or in the percent developing diabetes or returning to normal glucose tolerance . No subjects experienced increased serum or urinary calcium levels . At 12 months , A1C levels were significantly slightly less ( 0.2 % ) in the vitamin D group . CONCLUSIONS In individuals with prediabetes and hypovitaminosis D , doses of vitamin D supplementation design ed to raise serum 25-OHD levels into the upper-normal range for 1 year had no effect on insulin secretion , insulin sensitivity , or the development of diabetes  compared with placebo administration
CONCLUSIONS Supplementation with vitamin D showed no effect on adiposity measures in adults
CONTEXT The independent or interactive effects of vitamin D and calcium on adiposity remain inconclusive .
OBJECTIVE The objective of this systematic review and meta- analysis was to assess whether vitamin D and calcium supplements cause changes in adiposity .