Foods rich in cocoa have been known to help the heart, but researchers thought the added sugar, fat and calories cancelled out any good the chocolate might do.
But in small amounts, chocolate can be healthy, the new study by the University Hospital of Cologne, Germany shows. A quarter ounce of chocolate (6.8 grams) lowers blood pressure without negative side effects. A standard-sized chocolate bar weighs 100 grams.
Lowering blood pressure
"Regular intake of small amounts of dark chocolate can help to lower blood pressure," said Dr. Dirk Taubert, an author of the study, which recently appeared in the Journal of the American Medical Association.
Taubert and colleagues studied 44 adults with hypertension, but who were otherwise healthy, for nearly two years. One group of participants was given a 30-calorie square of dark chocolate with 30 mg of polyphenols. Others were given the same amount of white chocolate without polyphenols.
Polyphenols, a group of chemical substances found in dark choclate, were found to help lower hypertension.
Chocolate helps reduce blood pressure which in turn would reduce the risk of heart attacks and stroke, Taubert said in an interview with Reuters.
In the United States, more than 65 million adults have high blood pressure levels above 140/90, according to the National Heart, Lung and Blood Institute. An estimated 59 million more have pre-hypertension, which means blood pressure of 120/80 or above.
After 18 weeks, the dark chocolate group reported a three-point drop in systolic blood pressure (the top reading) and a two-point drop in diastolic blood pressure (the bottom reading.) The participants did not have weight gain, cholesterol increases or higher blood sugar.
"At first glance, this reduction may seem very low, but on a population basis, that means if everyone would experience this blood pressure reduction, the risk of cardiovascular death would be reduced about five percent" Taubert told Reuters.
An inexpensive fix
Taubert said researchers didn't buy any special brand for the study.
"It was the cheapest in the supermarket," he said.
While the chocolate used in the study contained 50 percent cocoa, dark chocolate with between 40 and 60 percent cocoa content should have the same beneficial effects, Taubert said.
That doesn't mean people should be shovelling candy bars into their mouths.
"One has to look at the whole picture," he said. "Dark chocolate may help as an addition to other lifestyle changes…like more sports or changing dietary habits, more fruit and vegetables and less fat and sugar intake."