Here's good news for the lovers of dark chocolate! It's good for the heart.

As dark chocolates contains high quantities of antioxidants called flavonoids, which prevent arteries from hardening, a study has found that eating a few squares a day could help prevent problems with blood flow. And remember these benefits are not shared by milk chocolate, because the milk interferes with the effect of the flavonoids.

In the study, tests were carried out on 20 smokers were asked to eat foods rich in antioxidants such as onions, apples and cabbage. And it was shown in the results that they have an increased risk of hardened arteries and heart disease.

They were then fed 2-ounce portions of different types of chocolate. After two hours, those who had eaten dark chocolate made up of at least 74 percent cocoa solids were found to have "significantly improved" blood flow. The effect lasted for eight hours.

Dr. Roberto Corti, who led the study at University Hospital, Zurich, said, "Only a small daily treat of dark chocolate may substantially increase the amount of antioxidant intake and beneficially affect vascular health." But Dr. Charmaine Griffith, of the British Heart Foundation, warned that chocolate was still extremely high in calories. "The key thing to remember about such studies is that chocolate is a bigger part of the problem than the solution," she said.