There is some evidence that calcium supplements can increase the risk of heart attacks. Calcium supplements are usually taken to treat or prevent bone disease, such as osteoporosis.
A review of studies found that calcium supplements increased the risk of heart disease, particularly in healthy, postmenopausal women. But other studies have said calcium supplements don't increase the risk.
More research is needed to know how calcium supplements affect a person's overall heart attack risk. What is known is that calcium from food sources, such as dairy products and leafy green vegetables, isn't a concern.
Taking calcium — with vitamin D — does provide a benefit for those who have too little calcium or bone loss. Ask your doctor if a calcium supplement is right for you.