No Need to Worry About Calcium and Your Heart
If you’ve been eyeing your calcium supplements with suspicion, worrying that what’s good for your bones might be bad for your heart, you can stop fretting. Last summer, a Ger-man study reported that people taking calcium supplements were almost twice as likely to suffer heart attacks as those not popping calcium pills (September 2012 Health & Nutrition Letter). But now new research using CT scans of participants’ hearts finds no asso-ciation between even the highest calcium intake from food plus supplements and coronary artery calcification—presumably the possible culprit in heart-attack risk.
Sarah L. Booth, PhD, a professor in Tufts’ Friedman School and a co-author of the new study, says, "The lack of any link between calcium intake and greater calcification should reassure those concerned by previous studies."
Booth and colleagues, led by Elizabeth Samelson, PhD, of the Institute for Aging Research at Hebrew SeniorLife and an asistant professor at Harvard Medical School, published their findings in the American Journal of Clinical Nutrition. The study involved 690 women and 588 men, average age 60, from the long-running Framingham Offspring Study. Participants were asked about their diet and supplement use, then underwent CT scans four years later to determine coronary artery calcification scores. An independent predictor of heart attack, those scores measure the severity of calci-fied plaque clogging the arteries in the heart.
Participants with the highest combined intake of calcium from diet and supplements actually had the best scores for coronary artery calcification. After adjustment for other factors, however, that association was not statistically significant. Samelson and colleagues concluded, "Our results do not support a significant detrimental effect of calcium intake on coronary artery calcification."
The upper range of combined calcium intake in the study was 3,000 milligrams per day, well above the latest recom-mendations from the Institute of Medicine (IOM). Echoing the latest findings, the IOM had already concluded that evidence does not support concerns about an adverse effect of calcium on cardiovascular disease. The IOM recommends 1,200 milligrams per day of calcium for women over 50 and men over 70, and 1,000 milligrams daily for men ages 51 to 70.
FOOD FIRST: "While our study has provided reassuring information when it comes to the safety of taking calcium supplements," Samelson adds, "I urge patients to contact their primary care physicians with any questions or concerns."
And it’s still best to try to get as much of your calcium as possible from food, Booth emphasizes. As the name implies, after all, supplements are meant to add to the nutrients you’re obtaining from your diet—not as a substitute for eating right.
If you do take calcium supplements, Tufts experts advise avoiding high-dose pills that deliver 500 or 1,000 milligrams more than the daily recommended amounts. Your body will also better absorb calcium in smaller doses throughout the day. (For more on getting the right amount of calcium safely, see our October 2012 Special Report.)