Calcium supplements taken by women as therapeutic arsenal against osteoporosis, a condition that makes bones brittle and fragile with advancing years, may be doing them more harm than good, claims a new study.
According to researchers, calcium compounds prescribed to post-menopausal women for building new bones and slowing bone destruction elevates their risk of heart attack and other cardiovascular issues.
Lead author of the study, Dr Ian Reid, a professor of medicine and endocrinology at the University of Auckland in New Zealand, stated, "There is a lack of consensus at the present time as to what recommendations should be regarding the use of calcium supplements.
"Our own recommendation is to critically review the use of calcium supplements, since the data in this paper suggests that they do more harm than good.
He added, "The cautious way forward seems to be to encourage people to obtain their calcium from the diet, rather than from supplements, since food calcium has not been shown to carry this increased risk of heart disease.”
"What we're suggesting is that we should move away from using supplements and instead, we should be encouraging people to get their calcium from their diet," --Ian Reid, professor of medicine and endocrinology at the University of Auckland.
Link between calcium supplementation and heart attacks examined
With the aim to examine the association between calcium supplementation and cardiovascular events, the researchers analyzed the data of a longitudinal Women's Health Initiative (WHI) study.
The study involved 16,700 women who were not taking calcium supplements at the onset of the study. The average age of the women was 63 years.
For the purpose of the study, the participants were randomly assigned to receive combined supplements of 1,000 mg of calcium and 400 IU of vitamin D pills daily.
The analysis found the risk of cardiovascular problems, particularly heart attacks rose by 13 to 22 percent in women who took combo supplements of calcium and vitamin D.
On the other hand the women who were taking the combined calcium and vitamin D supplements at the start of the trial exhibited no cardiovascular risk.
Reid stated, “Even though these increases are relatively small, we think they're significant, firstly, because a lot of people around the world take calcium and vitamin D, and secondly because what the data in these databases suggest is that we're probably going to cause more heart-related events than we prevent fractures.”
A plausible explanation
Though the link between calcium supplements and increase in heart attack risk is ambiguous, researchers theorize that extra calcium circulating in the blood hardens the arteries which in turn triggers heart attack.
Experts, advise women to steer clear from calcium supplements and move toward eating calcium-rich food as part of a normal balanced diet.
According to them, calcium from food sources is absorbed slowly so that there is a steady trickle of calcium into the bloodstream.
Ried stated, "What we're suggesting is that we should move away from using supplements and instead, we should be encouraging people to get their calcium from their diet.
"We should rely on our diet to source our calcium. And for people who are at a high risk of fracture, they should be relying on medicines to decrease their fracture risk, not taking supplements.”
The study appears online in the 'British Medical Journal.'
A little about osteoporosis
Osteoporosis is a disease characterized by low bone mass and loss of bone tissue that may lead to weak and fragile bones.
It is very common in post-menopausal women because the oestrogen levels drop and cells that tear down old bone become over-active.