Supplemental Calcium May Increase CVD Risk

A high intake of supplemental calcium appears to be associated with an increased risk of cardiovascular disease (CVD) death in men but not in women, according to a report published online in JAMA Internal Medicine.

Calcium supplementation has become widely used, especially among the elderly population, because of its proposed bone-health benefits. However, beyond calcium’s established role in the prevention and treatment of osteoporosis, its health effect on nonskeletal outcomes, including cardiovascular health, remains largely unknown and has become “increasingly contentious,” the authors wrote.

Qian Xiao, PhD, of the National Cancer Institute, and colleagues examined whether the intake of dietary and supplemental calcium was associated with mortality from total CVD, heart disease, and cerebrovascular diseases. The study participants were 388,229 men and women aged 50 to 71 from six states and two metropolitan areas who were part of the National Institutes of Health-AARP Diet and Health Study from 1995 through 1996.

“In this large, prospective study, we found that supplemental but not dietary calcium intake was associated with an increased CVD mortality in men but not in women,” the authors concluded.

During an average 12 years of follow-up, 7,904 CVD deaths in men and 3,874 CVD deaths in women were identified, and 51% of men and 70% of women used supplements containing calcium. Compared with nonsupplement users, men with an intake of supplemental calcium of more than 1,000 mg/day had an increased risk of total CVD death (risk ratio of 1.20), more specifically with heart disease (risk ratio of 1.19), but not significantly with cerebrovascular disease death (risk ratio of 1.14).

For women, supplemental calcium intake wasn’t associated with CVD, heart disease, or cerebrovascular disease death. Dietary calcium intake also wasn’t associated with CVD death in men or women.

“Whether there’s a sex difference in the cardiovascular effect of calcium supplements warrants further investigation. Given the extensive use of calcium supplements in the population, it’s of great importance to assess the effect of supplemental calcium use beyond bone health,” the authors concluded.

Source: American Medical Association