LONDON: A few squares of chocolate a day can almost halve the risk of heart attack death in some people, says a study. But scientists warn that eating more of it could be bad for health.

Researchers have known for nearly two decades that dark chocolate, rich in chemicals called flavonoids, lowers blood pressure and has other beneficial effects on blood flow.

The latest study on 139 people by Diane Becker, a professor at The Johns Hopkins University School of Medicine and Bloomberg School of Public Health and other researchers, identified the effect of normal, everyday doses of chocolate found in ordinary foods.

They found that just a few squares of chocolate a day can almost halve the risk of heart attack death in some men and women by decreasing the tendency of platelets to clot in narrow blood vessels, reported Newswise wire. “Eating a little bit of chocolate or having a drink of hot cocoa as part of a regular diet is probably good for personal health, so long as people don’t eat too much of it, and too much of the kind with lots of butter and sugar,” said Becker.

The chemical in cocoa beans has a biochemical effect similar to aspirin in reducing platelet clumping, which can be fatal if a clot forms and blocks a blood vessel, causing a heart attack, the researcher said.

Becker cautioned that her work is not intended as a prescription to gobble up large amounts of chocolate candy, which often contains diet-busting amounts of sugar, butter and cream. But as little as two tablespoons a day of dark chocolate — the purest form of the candy made from the dried extract of roasted cocoa beans — may be just what the doctor ordered. “We have to be careful to emphasise that one single healthy dietary practice cannot be taken alone, but must be balanced with exercise and other healthy lifestyle practices that impact the heart,” said study co-author Nauder Faraday, an associate professor at Hopkins.