Evidence from trials with vitamin D and /or calcium supplementation suggests that combined vitamin D and calcium supplementation may have a role in the prevention of type 2 DM only in population s at high risk ( i.e. glucose intolerance ) .
Vitamin D and calcium insufficiency may negatively influence glycemia , whereas combined supplementation with both nutrients may be beneficial in optimizing glucose metabolism
CONTEXT Altered vitamin D and calcium homeostasis may play a role in the development of type 2 diabetes mellitus ( type 2 DM ) .
Effects of calcium and dairy on body composition and weight loss in African-American adults.
OBJECTIVE Our objective was to determine the effects of dairy consumption on adiposity and body composition in obese African Americans . RESEARCH METHODS AND PROCEDURES We performed two r and omized trials in obese African-American adults . In the first ( weight maintenance ) , 34 subjects were maintained on a low calcium ( 500 mg/d)/low dairy ( < 1 serving/d ) or high dairy ( 1200 mg Ca/d diet including 3 servings of dairy ) diet with no change in energy or macronutrient intake for 24 weeks . In the second trial ( weight loss ) , 29 subjects were similarly r and omized to the low or high dairy diets  and placed on a caloric restriction regimen ( -500 kcal/d ) . RESULTS In the first trial , body weight remained stable for both groups throughout the maintenance study . The high dairy diet result ed in decreases in total body fat ( 2.16 kg , p < 0.01 ) , trunk fat ( 1.03 kg , p < 0.01 ) , insulin ( 18.7 pM , p < 0.04 ) , and blood pressure ( 6.8 mm Hg systolic , p < 0.01 ; 4.25 mm Hg diastolic , p < 0.01 ) and an increase in lean mass ( 1.08 kg , p < 0.04 ) , whereas there were no significant changes in the low dairy group . In the second trial , although both diets produced significant weight and fat loss , weight and fat loss on the high dairy diet were approximately 2-fold higher ( p < 0.01 ) , and loss of lean body mass was markedly reduced ( p < 0.001 ) compared with the low dairy diet . DISCUSSION Substitution of calcium-rich foods in isocaloric diets reduced adiposity and improved metabolic profiles in obese African Americans without energy restriction or weight loss and augmented weight and fat loss secondary to energy restriction
Evidence from trials with vitamin D and /or calcium supplementation suggests that combined vitamin D and calcium supplementation may have a role in the prevention of type 2 DM only in population s at high risk ( i.e. glucose intolerance ) .
Vitamin D and calcium insufficiency may negatively influence glycemia , whereas combined supplementation with both nutrients may be beneficial in optimizing glucose metabolism
CONTEXT Altered vitamin D and calcium homeostasis may play a role in the development of type 2 diabetes mellitus ( type 2 DM ) .