Review: No clear link for calcium supplements, CVD

(HealthDay)—Calcium supplements, taken within recommended levels, can be considered safe for the heart, according to new guidelines and an evidence review published online Oct. 25 in the Annals of Internal Medicine.

To develop the new guidelines, the National Osteoporosis Foundation commissioned an updated research review, done by independent researchers at the Tufts University School of Medicine in Boston. The researchers analyzed 31 studies. Four of them were clinical trials, where older adults (mostly women) were randomly assigned to take calcium, with or without vitamin D.

None of those trials showed that supplement users had higher risks of cardiovascular disease, stroke, or death than participants given placebo pills, the researchers found. The rest of the studies the Tufts team analyzed were observational: They looked at the relationship between people's calcium intake, from diet or supplements, and their risk of cardiovascular disease or stroke. Again, the researchers found the studies showed no consistent connection between higher calcium intake and higher cardiovascular risks.

"The preponderance of evidence does not support cardiovascular adverse effects" from calcium supplements, write the authors of an accompanying editorial. But the editorial authors noted that calcium supplements do have side effects and they urged people to take moderate supplement doses, but only if their diets are deficient in calcium.

The National Osteoporosis Foundation funded the review through a grant from Pfizer Consumer Healthcare, which makes calcium supplements.