Swiss researchers tracked 24,000 men and women for 11 years. They found that people who regularly took a calcium supplement increased their risk for heart attack by 86%. But here’s the important distinction: Dietary calcium was not linked to an increased risk for heart disease. In fact, people who ingested the most calcium through their diets actually lowered their risk for heart attack by 31%. What’s going on here? It may have to do with the level of calcium in your blood, says Ian Reid, MD, a professor of medicine and endocrinology at the University of Auckland in New Zealand, whose past research has linked calcium to heart disease risk. “Calcium in the diet has very little impact on blood calcium levels, whereas calcium supplements cause abrupt increases in blood calcium over a period of a few hours,” Dr. Reid says. Those blood-calcium spikes may lead to damaged arteries or blockages in the form of calcium deposits, he says. Although the increase in heart attack risk associated with calcium supplements was significant, the study authors point out that the overall risk within the study group was still relatively low—just 354 of the 24,000 participants suffered a heart attack during the follow up period. More research is needed to fully understand how calcium supplements may affect heart health. So what should you do in the meantime? Talk to your doctor about stopping your calcium supplements, says Dr. Reid. “Calcium in tablet form may do more harm than good,” he says. Instead, focus on meeting your daily calcium needs (1,000 milligrams for women age 50 and under; 1,200 for those 51 and over) through your diet with foods like cheese, yogurt, milk, salmon, and spinach. Check out this full list of great sources of dietary calcium. More from Prevention: The Bone Scandal
