Calcium is good for your bones and everything, but taking calcium supplements is damaging to your heart, says a new study published in Journal of the American Heart Association.
This finding is based on the evaluation of medical tests of around 2,700 individuals who participated in a heart disease study; the information, collected over a decade, was used by a team of researchers from Johns Hopkins Medicine who wanted to investigate the consumption of calcium supplements with respect to the circulatory system because of past studies suggesting adverse effects. It is to be noted that the research is about calcium supplements, and not calcium itself which is, otherwise, needed by the body. But, too much of it would not be as beneficial as one would think.
“When it comes to using vitamin and mineral supplements, particularly calcium supplements being taken for bone health, many Americans think that more is always better,” says Erin Michos, one of the researchers. “But our study adds to the body of evidence that excess calcium in the form of supplements may harm the heart and vascular system.”
Michos and his team also wanted to understand as to what happens to this calcium in the body as other research works show that it is neither excretednor incorporated into bones. Where does the calcium go, then? The researchers suspect that it might be building up in soft tissues of the body. Furthermore, scientists have discovered that plaques made of calcium will often accumulate in the aorta and other arteries as a person ages; this will obstruct blood flow, eventually leading to an increased likelihood of heart attacks. Therefore, taking supplements might further raise this risk.
To find answers to their queries, the team categorised the participants according to their consumption of calcium supplements: two groups were compared, those taking only dietary calcium and those consuming calcium supplements (46% of all the participants). The findings show that the second group had a greater risk of developing heart disease: this was concluded from a 22% greater risk of having their coronary artery calcium scores increase beyond zero over the ten years of the study.
“There is clearly something different in how the body uses and responds to supplements versus intake through diet that makes it riskier,” says co-author John Anderson. “It could be that supplements contain calcium salts, or it could be from taking a large dose all at once that the body is unable to process.”
Another interesting finding pointing at the harmful nature of calcium supplements is that participants with the highest dietary calcium intake (beyond 1,022 mg of calcium daily) had no increase in the risk of heart disease in the ten years of the study. So, the problem would be in taking calcium supplements, and not in consumption calcium itself.
“Based on this evidence, we can tell our patients that there doesn’t seem to be any harm in eating a heart-healthy diet that includes calcium-rich foods, and it may even be beneficial for the heart,” says Michos. “But patients should really discuss any plan to take calcium supplements with their doctor to sort out a proper dosage or whether they even need them.”
The authors of the new paper recommend people intending to take the supplements to consult physicians before doing so. On the other hand, they add that their findings only point at a link between calcium supplements and atherosclerosis, without revealing the cause and effect.