Research that shows just one small square of chocolate a day can lower your blood pressure and reduce your risk of heart disease. The study is published online in the European Heart Journal.
Researchers in Germany followed 19,357 people, aged between 35 and 65, for at least ten years and found that those who ate an average of 7.5 grams (about .25oz) a day, had lower blood pressure and a 39% lower risk of having a heart attack or stroke compared to those who ate the least amount of chocolate, an average of 1.7 grams a day. The difference between the two groups amounts to six grams of chocolate: the equivalent of less than one small square of a 3.5 ounce bar.
The people in the study were participants in the Potsdam arm of the European Prospective Investigation into Cancer (EPIC). They received medical checks, including blood pressure, height and weight measurements at the start of the study between 1994-1998, and they also answered questions about their diet, lifestyle and health. The researchers asked a sub-set of 1,568 participants to recall their chocolate intake over a 24-hour period and to indicate which type of chocolate they ate. In this sub-set, 57% ate milk chocolate, 24% dark chocolate and 2% white chocolate.
In follow-up questionnaires, sent out every two or three years until December 2006, the study participants were asked whether they had had a heart attack or stroke, information which was subsequently verified by medical records from general physicians or hospitals. Death certificates from those who had died were also used to identify heart attacks and strokes.
People in the top quartile had a 27% reduced risk of heart attacks and nearly half the risk (48%) of strokes, compared with those in the lowest quartile.
The researchers believe that flavanols in cocoa may be the reason why chocolate seems to be good for people's blood pressure and heart health; and since there is more cocoa in dark chocolate, dark chocolate may have a greater effect. In fact, dark chocolate with a cocoa content of at least 70%, reduces oxidative stress and improves vascular and platelet function. We may have a new cliche - a truffle a day keeps the blood pressure at bay.