Calcium supplements that many women take to boost bone health increase their risk for heart disease, a new study has found.
The results show that calcium supplements make people more prone to plaque buildup in arteries, which contributes to the risk of a heart attack. The study, published in the Journal of the American Heart Association, is the latest salvo in a nearly decade-long debate about whether the supplements do more harm than good.
The researchers said their findings give patients reason to use caution when taking the supplements. It is better to get calcium from food such as dairy products, leafy green vegetables and fortified cereal and juices, they said.
When calcium plaque builds up in the arteries, it inhibits blood flow, increasing heart-attack risk.
“We think the body metabolizes supplements and dietary calcium differently,” said Erin Michos of the Ciccarone Center for the Prevention of Heart Disease at the Johns Hopkins University medical school. “If you are worried about your bones, then get your calcium through food.” She said the study adds to growing evidence that calcium supplements are bad for the heart.
But the Council for Responsible Nutrition, which represents manufacturers of dietary supplements, said just as many studies show the opposite and pointed to evidence in the study that people who get a high dose of calcium from a mix of foods and supplements had the lowest risk of calcification in the coronary artery.
The study was prompted in large part because the scientists wanted to build on previous research by others that found calcium supplements never actually make it to a patient’s bones and instead accumulate in soft tissue and muscles, such as the heart.
The study used data from more than 6,000 people to look at the risk factors and characteristics of cardiovascular disease. Michos and fellow researchers focused on 2,742 participants who had CT scans taken at the study’s start and 10 years later. They found that supplement users were 22 percent more likely to develop heart disease over the decade.
The research did find that those who consumed the highest levels of calcium — from foods and supplements — were 27 percent less likely to develop heart disease.
“A lot of women are taking calcium supplements because they think it is good for their body,” Michos said. “We need to get the message out . . . that they need to take caution with the supplements they take into their bodies.”