There’s no evidence suggesting that a calcium-rich diet causes heart problems. Rachel James

“People taking calcium supplements to mitigate their risk of developing bone disease (osteoporosis) may be doing more harm to their health than good. That’s because a growing body of research shows the supplements confer little benefit and increase the risk of developing heart disease.

“Calcium supplements have also traditionally been thought to reduce the risk of heart attacks because they produce small beneficial changes in both blood pressure and blood cholesterol levels. We set out to test this idea in a trial we had originally designed to check the effect of calcium supplements on fractures and bone density.

“To our surprise, what we discovered was that heart attacks were actually more common in the (randomly selected) women who received calcium supplements than those who had randomly been given inactive tablets.

“When we published this study in the British Medical Journal in 2008, it caused widespread surprise among doctors working in the area, as well as the general public. So to test whether this was the true effect of calcium supplements, we decided to do a meta-analysis of studies about taking them.

“First, we contacted all the researchers who had carried out large trials of calcium supplements in the past to see whether they’d kept records of the medical problems that occurred in the course of the trials.

“Data were available from 93% of trial subjects (almost 12,000 people) and these confirmed our finding that women who received calcium tablets in the studies had a 20% to 30% increase in heart attack risk.

“We subsequently added to this database the results from other trials in which the intervention was calcium and vitamin D, rather than calcium alone. This showed the same effect – a 25% increase in the risk of heart attacks and a 15% increase in the risk of stroke.

“These results were based on almost 29,000 people participating in research and so were much more reliable than the results we had published previously.” To continue reading this article from The Conversation, click here.