Sweet Science

NEW ORLEANS, March 26, 2007 — -- Anyone looking for an excuse to order a chocolatey dessert will find one in new research showing cocoa can boost artery function.

In a small study, Yale University researchers found that people who ate chocolate showed increased arterial blood flow, with marginally better results for people who ate unsweetened chocolate as compared with those who had the sweetened form.

"Chocolate contains flavenoids that are antioxidant molecules that may prevent damage in the arteries," said Dr. Chris Cannon, a cardiologist at Brigham and Women's Hospital, who was not involved in the study.

The researchers gave participants eight ounces of chocolate and measured blood flow through an artery in the upper arm. They found it improved significantly in those who ate chocolate, by 2.4 percent among those who had the unsweetened chocolate and 1.5 percent in those who ate the sweetened form. Researchers announced the findings at the American College of Cardiology Conference in New Orleans.

Though it's good news for chocolate lovers, experts caution against overindulging. "There's a potential benefit for heart arteries, but chocolate in all its candy bar forms has lots of sugar and fat and so that may counterbalance the benefit of the cocoa and flavenoids," said Cannon.

Another concern is that the benefits appear to be transient. "We know that the effects of cocoa on vascular health are relatively short-lived, lasting one to two hours, and six hours later the effects diminish," said Dr. Robert S. Rosenson of the University of Michigan.

He says in order to get the full benefits of cocoa and avoid potentially harmful doses of fat and sugar, scientists might consider packaging cocoa in tablet form -- though he admits it's a much less appetizing option.