Aug. 29, 2011 -- A new review of previously published studies adds weight to the claim that chocolate is good for the heart.

Taken together, five of seven studies included in the review linked high chocolate consumption with a 37 percent reduction in cardiovascular disease risk, a 31 percent reduction in diabetes risk and a 29 percent reduction in stroke risk when compared to low chocolate consumption.

"Although over-consumption can have harmful effects, the existing studies generally agree on a potential beneficial association of chocolate consumption with a lower risk of cardiometabolic disorders," Adriana Buitrago-Lopez of the University of Cambridge in the U.K. and colleagues reported today in BMJ.

The findings held up even when factors such as age, diet, physical activity, body mass index and smoking were controlled for. But the review stopped short of concluding that chocolate itself makes people healthier.

"This paper merely shows us that the association between habitual intake of chocolate and lower cardiometabolic risk is 'statistically robust,'" said Dr. David Katz, director of medical studies in public health at Yale University. "But what if happier people eat more chocolate, and are at lower cardiometabolic risk because they are happier? This paper cannot address such subtleties."

The review included data collected from more than 114,000 people. But the large numbers don't prove cause and effect, Katz said. The review does, however, support chocolate as a healthful indulgence -- in moderation, of course.

This is a wonderful example of the opportunity to love food that loves us back," said Katz. "However, too much of a good thing is no longer a good thing."

Chocolate for Health: What Dose Is Best?

Katz, who has published studies on the health effects of chocolate, said the next step is to establish a therapeutic window similar to that for red wine.

"Our conclusion is that dark chocolate -- 60 percent cocoa or higher -- and liquid cocoa have clear, potential benefits in terms of overall cardiac risk, but that we don't yet know enough about optimal dosing to best use this food 'as medicine,'" Katz said.