Ten grams of dark chocolate a day, or about one-third of a chocolate bar, may reduce the risk of dying from heart disease and stroke by half, new research suggests.

Dutch men who regularly consumed cocoa, from Mars and Milky Way bars to full-fat chocolate milk, had significantly lower blood pressure than those who did not.

And men with the highest cocoa consumption (4.2 grams per day, or equal to 10 grams of chocolate) were half as likely as the others to die from cardiovascular disease.

They were also less likely to die of any cause in the study.