['Calcium intake is a potential factor influencing weight gain and may reduce body weight, but the evidence for this in children is conflicting. The aim of this study was to use data from randomized controlled trials to determine whether calcium supplementation in healthy children affects weight or body composition.', 'This study is a systematic review. We identified potential studies by searching the following electronic bibliographic databases: CENTRAL, MEDLINE, EMBASE, CINAHL, AMED, MANTIS, ISI Web of Science, Food Science and Technology Abstracts, and Human Nutrition up until April 1, 2005 and hand-searched relevant conference abstracts. Studies were included if they were placebo-controlled randomized controlled trials of calcium supplementation, with at least 3 months of supplementation, in healthy children and with outcome measures including weight. Meta-analyses were performed using fixed effects models and weighted mean differences for weight and height and standardized mean differences (SMDs) for body composition measures.', 'There were no statistically significant effects of calcium supplementation on weight [+0.14 kg; 95% confidence interval (CI), -0.28, +0.57 kg], height (+0.22 cm; 95% CI, -0.30, +0.74 cm), body fat (SMD, +0.04; 95% CI, -0.08, +0.15), or lean mass (SMD, +0.14; 95% CI, -0.03, +0.31).'] Do calcium supplements in healthy children affect weight gain , height , or body composition?