title: Effects of calcium supplementation on body weight and adiposity in overweight and obese adults: a randomized trial.
abstract: BACKGROUND
  Some data suggest that increasing calcium intake may help prevent weight gain.
  
  
  OBJECTIVE
  To test the hypothesis that calcium supplementation can prevent weight gain in persons who are overweight or obese.
  
  
  METHODS
  Randomized, placebo-controlled trial. Randomization was computer-generated, and allocation was assigned by pharmacy personnel who prepared intervention and placebo capsules. Participants, providers, and those who assessed outcomes were blinded to study group assignment.
  
  
  METHODS
  Single research center.
  
  
  METHODS
  340 overweight (body mass index [BMI], 25 to <30 kg/m(2)) and obese (BMI > or =30 kg/m(2)) adults (mean age, 38.8 years [SD, 10.5]).
  
  
  METHODS
  Calcium carbonate (elemental calcium, 1500 mg/d) (n = 170) or placebo (n = 170) with meals for 2 years.
  
  
  METHODS
  Changes in body weight and fat mass (primary outcomes).
  
  
  RESULTS
  Seventy-five percent of participants completed the trial (78% received calcium; 73% received placebo). There were no statistically or clinically significant differences between the calcium and placebo groups in change in body weight (difference, 0.02 kg [95% CI, -1.64 to 1.69 kg]; P = 0.98), BMI (difference, 0.32 kg/m(2) [CI, -0.41 to 1.02 kg/m(2)]; P = 0.39), or body fat mass (difference, 0.39 kg [CI, -1.04 to 1.92 kg]; P = 0.55). Parathyroid hormone concentrations decreased in the calcium group compared with the placebo group (difference, -0.71 pmol/L [CI, -1.28 to -0.13 pmol/L]).
  
  
  CONCLUSIONS
  The study took place at a research center, and its sample was mostly women.
  
  
  CONCLUSIONS
  Dietary supplementation with elemental calcium, 1500 mg/d, for 2 years had no statistically or clinically significant effects on weight in overweight and obese adults. Calcium supplementation is unlikely to have clinically significant efficacy as a preventive measure against weight gain in such patients.
authors.affiliation: National Institutes of Health, Hatfield Clinical Research Center, Bethesda, Maryland 20892-1103, USA. jy15i@nih.gov
authors.forename: Jack A
authors.initials: JA
authors.lastname: Yanovski
authors.forename: Shamik J
authors.initials: SJ
authors.lastname: Parikh
authors.forename: Lisa B
authors.initials: LB
authors.lastname: Yanoff
authors.forename: Blakeley I
authors.initials: BI
authors.lastname: Denkinger
authors.forename: Karim A
authors.initials: KA
authors.lastname: Calis
authors.forename: James C
authors.initials: JC
authors.lastname: Reynolds
authors.forename: Nancy G
authors.initials: NG
authors.lastname: Sebring
authors.forename: Teresa
authors.initials: T
authors.lastname: McHugh
mesh_terms: D050154:Adiposity; D000293:Adolescent; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002119:Calcium Carbonate / Q000008:administration & dosage*; D002136:Calcium, Dietary / Q000008:administration & dosage*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000178:diet therapy*; D050177:Overweight / Q000178:diet therapy*; D010349:Patient Compliance; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires; D015431:Weight Loss; D055815:Young Adult
chemical_list: D002136:Calcium, Dietary; D002119:Calcium Carbonate