A meta-analysis published in the American Journal of Clinical Nutrition (December 2007; 86(6):1579–1580) examined the relationship between calcium supplementation and fracture risk. Meta-analyses synthesize data from multiple studies to evaluate overall trends and consistency of findings across large populations.
In this analysis, researchers from Harvard reviewed seven studies involving more than 170,000 women, among whom nearly 3,000 hip fractures were documented, as well as five studies involving more than 68,000 men with over 200 documented hip fractures. The authors reported that calcium supplementation at doses of approximately 300 mg per day was not associated with a reduced risk of hip fracture.
The analysis also noted that in clinical trials using higher calcium doses—ranging from 800 to 1,600 mg per day—no significant reduction in hip fractures or other non-vertebral fractures was observed when calcium was given alone. However, the authors reported that combining calcium with vitamin D was associated with a reduction in fracture risk, suggesting that vitamin D status may play an important role in skeletal outcomes.
