High doses of calcium supplements may raise men's heart risk

The study, involving 388,000 people, found men taking calcium supplements of more than 1,000mg a day had a greater chance of suffering heart disease and dying from it.

However, those achieving high-calcium diets solely through food or drink were not at extra risk, said researchers from the National Cancer Institute in the US.

It was the way supplements increase the levels of calcium circulating in the blood which appeared to have an adverse effect on the cardiovascular system, the 'Daily Mail' reported.

Experts believe higher blood levels lead to hardening of the arteries, which can cause heart attacks.

Researchers followed men and women aged 50 to 71 over an average of 12 years. They recorded 7,904 deaths in men from cardiovascular disease and 3,874 deaths in women.

Supplements containing calcium were used by 51 per cent of men and 70 per cent of women.

Men taking 1,000mg or more in calcium supplements a day had an almost 20 per cent higher rate of heart disease and death than those who did not take supplements.

Women had no such extra risk, although some previous trials have found a link, the study reported in JAMA Internal Medicine said.

"Whether there is a sex difference in the cardiovascular effect of calcium supplements warrants further investigation. Given the extensive use of calcium supplements in the population, it is of great importance to assess its use beyond bone health," the report said.