Calcium supplements without vitamin D might raise risk for myocardial infarction in individuals with moderately high dietary calcium intake.
Calcium supplements often are recommended for preventing osteoporosis. Observational studies suggest that high calcium intake can protect against vascular disease, whereas one 5-year randomized controlled trial (RCT) indicated that women who take calcium supplements might have excess risk for myocardial infarction (MI; JW Womens Health Feb 7 2008). To evaluate further the relation between calcium supplements and cardiovascular risk, investigators performed a meta-analysis of 11 RCTs involving calcium supplementation (≥500mg daily) without vitamin D in 12,000 men and women aged >40.
During follow-up, risk for incident MI rose by 31% in participants who received calcium supplements compared with those who received placebo (hazard ratio, 1.31; …