8 randomized controlled trials (30,970 adults) comparing calcium with vitamin D supplementation against no supplementation or a placebo in an adult population were included in this study. The purpose of this meta-analysis was to analyze the effect of calcium and vitamin D supplementation on fracture prevention (total and hip) in adults. The results displayed a significant reduction of 14% in total fractures and a significant reduction of 30% in hip fractures, with calcium and vitamin D supplementation, when compared to a placebo. Furthermore, results were robust to sensitivity analyses and were consistent in the subgroup analyses conducted by adherence to assigned treatment, use of personal supplements, community-dwelling and institutionalized patients.