A high intake of supplemental calcium appears to be associated with an increased risk of CVD death in men but….
In a study of more 388,000 participants between the ages of 50 and 71 years, they found that 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.
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 non-skeletal outcomes, including cardiovascular health, remains largely unknown and has become "increasingly contentious," the authors write in the study background.
Qian Xiao, Ph.D., of the National Cancer Institute, Bethesda, Md., and colleagues examined whether the intake of dietary and supplemental calcium was associated with mortality from total CVD, heart disease and cerebrovascular diseases. "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 conclude.
During an average 12 years of follow-up, 7,904 CVD deaths in men and 3,874 CVD deaths in women were identified and supplements containing calcium were used by 51 percent of men and 70 percent of women. Compared with non-supplement 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 [RR], 1.20), more specifically with heart disease (RR, 1.19), but not significantly with cerebrovascular disease death (RR, 1.14).
For women, supplemental calcium intake was not associated with CVD death, heart disease death or cerebrovascular disease death. Dietary calcium intake also was not associated with CVD death in men or women.
"Whether there is a sex difference in the cardiovascular effect of calcium supplement warrants further investigation. Given the extensive use of calcium supplement in the population, it is of great importance to assess the effect of supplemental calcium use beyond bone health," the authors conclude.
In a related commentary, Susanna C. Larsson, Ph.D., of the Karolinska Institutet, Stockholm, Sweden, writes, "Meanwhile, a safe alternative to calcium supplements is to consume calcium-rich foods, such as low-fat dairy foods, beans and green leafy vegetables, which contain not only calcium but also a cocktail of essential minerals and vitamins." "These non-dairy food sources of calcium have the added health benefits and have recently been reported to improve glycemic control in persons with diabetes. The paradigm ‘the more the better’ is invalid for calcium supplementation."
JAMA Intern Med. Published online February 4, 2013. doi:10.1001/jamainternmed.2013.3283.