Flavanols are a type of antioxidant compound found in high concentrations in dark chocolate.  Brian Buijsse, from the German Institute of Human Nutrition (Nuthetal, Germany), and colleagues studied 19,357 people, ages 35 to 65 years, enrolled in the Potsdam arm of the European Prospective Investigation into Cancer (EPIC) study. Following the subjects for at least ten years, the team found that those who ate the most amount of chocolate -- an average of 7.5 grams a day -- had lower blood pressure and a 39% lower risk of having a heart attack or stroke, as compared to those who ate the least amount of chocolate -- an average of 1.7 grams a day. Noting that the difference between the two groups amounted to six grams of chocolate, or the equivalent of less than one small square of a 100g bar, the researchers explain that: “To put it in terms of absolute risk, if people in the group eating the least amount of chocolate … increased their chocolate intake by six grams a day, 85 fewer heart attacks and strokes per 10,000 people could be expected to occur over a period of about ten years.” They conclude that: “Chocolate consumption appears to lower [cardiovascular disease] risk, in part through reducing [blood pressure].”