A hot mug of cocoa is better homemade medicine for blood pressure and heart disease than a spot of tea, according to an analysis of studies that was released today.

Cocoa, the bean that flavors chocolate, lowers pressure as much as some medications, while neither black nor green tea has much effect on the force of blood on vessel walls, said scientists led by Dirk Taubert, a pharmacologist at the University Hospital of Cologne in Germany.

Like some fruits and vegetables, both cocoa and tea contain molecules called phenols that have been linked to lower blood pressure. The analysis of 10 studies suggests that, unlike those in tea, the phenols in cocoa are potent enough for recommendation as part of a heart-healthy diet, the researchers said in the study published in the Archives of Internal Medicine.

But there is a caveat.

"Any dietary advice must account for the high sugar, fat and calorie intake with most cocoa products," they said. "Rationally applied, cocoa products might be considered part of dietary approaches to lower hypertension risk."

People eating cocoa to improve heart health should be wary of the fat and calories in most chocolate candies, said Naomi Fisher, a Harvard Medical School endocrinologist who wasn't involved in the analysis. In one of the studies, chocolate added an extra 480 calories a day to the people's diets, she said.

"We have to be responsible and not have Americans or world citizens consuming chocolate because 'it's good for you,'" she said by phone. "The first, second and third ingredients of many chocolate confections are sugar, oils and fats."

About 65 million U.S. adults have abnormally high blood pressure, according to the National Institutes of Health. Doctors frequently prescribe both generic and branded drugs to reduce pressure that can damage blood-vessel walls and increase the risk of heart attack, stroke and other forms of cardiovascular disease, the No. 1 killer in the country.

Taubert and his colleagues combined results from five studies of cocoa and blood pressure and five of tea's effects that involved a total of 516 people. All the studies took place between 1966 and 2006 — including eight since 2001 — enrolled at least 10 subjects each and lasted a week or longer.

Blood pressure is measured once when the heart is pumping and again when it relaxes between beats. Measured in milligrams of mercury, the pressure should register 140 during beats and 90 between.

Among 87 people who consumed cocoa, the pressure during beats, called systolic pressure, was 4.7 milligrams of mercury lower than that of 86 people who weren't consuming it. In cocoa drinkers, the relaxed pressure dropped an average of 2.8 milligrams of mercury lower.

The effect is similar to that of drugs such as beta-blockers and diuretics used to control blood pressure, the study said. Such reductions would be expected to reduce the risk of stroke by about 20 percent, death from heart disease by 10 percent, and death from any cause by 8 percent, the scientists said in the study.

By comparison, average blood pressure was no different among 171 people who drank tea during the studies than among 172 people who didn't drink the beverage. Tea contains a different class of phenols, called flavan-3-ols, than those in cocoa, which are called procyanids.

"Different plant phenols must be differentiated with respect to their blood pressure-lowering potential and thus cardiovascular disease prevention," the authors concluded.