Calcium Supplementation Is Associated with Excess Risk for Myocardial Infarction

Evidence suggests that calcium supplements hasten vascular calcification and increase mortality in patients with kidney failure and raise risk for myocardial infarction (MI) in healthy older women. To further investigate the association between supplemental calcium and adverse cardiovascular events, researchers conducted a meta-analysis of 15 double-blind, randomized trials in which participants (mean age at baseline, >40) received calcium supplements (≥500 mg daily) or placebo.

Patient-level data were available for five trials involving >8000 participants (77% women; median follow-up, 3.6 years). MIs occurred in 143 participants randomized to calcium supplements and 111 randomized to placebo — a significant difference. Calcium supplementati…