A new study finds women who took calcium as part of the study had a modest 13 to 22 percent increased risk of cardiovascular problems, particularly heart attacks.
Authors of the study in the journal BMJ say more than half the women in the study were already taking their own calcium supplements on top of what they had been prescribed for the trial. They believe that could have clouded the results.
Some experts say the cautious way forward would be to obtain calcium from diet rather than from supplements. but they're calling for more research.