A team of researchers from the University Hospital of Cologne analyzed data from previous studies that looked at the benefits of tea and cocoa. They found eating foods rich in cocoa resulted in lower blood pressure levels -- enough to match levels reached with medication.

Their report covered exactly 10 studies on cocoa with a total of 173 participants, a third of whom had high blood pressure and were followed for a two-week period, and five tea studies with 343 participants, followed for a four-week period.

The fall in blood pressure credited to cocoa could be expected to reduce the risk of strokes and heart attacks by 10-20 percent, the report said.

The benefits are believed to come from compounds known as polyphenols (or flavonoids), explained Dr. Dirk Taubert, a senior lecturer in pharmacology and toxicology at Cologne and leading author of the report.

While tea and cocoa are both rich in polyphenols, cocoa contains more of a type called procyanids. This suggests that different plant phenols may contribute differently to lowering blood pressure. Compared to cocoa phenols, tea phenols appear to be less effective.

However, the researchers cautioned that while their findings should not be taken as a widespread recommendation for higher cocoa intake to decrease blood pressure, it appears reasonable that phenol-rich cocoa products could be substituted for other high calorie and high fat desserts.

Drug treatment is the basis of blood pressure control, Taubert said, and it should always be accompanied by lifestyle measures such as exercise and proper diet. "Rationally applied, cocoa products may be part of such an anti-hypertensive diet," he added.