Brian Buijsse of the National Institute for Public Health and the Environment in Bilthoven and his colleagues measured the cocoa intake of 470 men between 1985 and 2000 as part of the Zutphen Elderly Study, a longitudinal look at nearly 1,000 Dutch men between 65 and 84 years of age. The nutrition experts identified 24 cocoa-containing foods that the elderly men ate, ranging from dark chocolate bars to chocolate spreads. They summed the total amount of cocoa each consumed and came up with a grams-per-day measurement, which they used to separate the men into three groups: those who ate little chocolate, a modest amount, and the most.
Among those who ate the most chocolate--averaging more than four grams a day--average systolic and diastolic blood pressure was 3.7 and 2.1 millimeters of mercury lower than their chocolate-spurning peers. This result did not hold true for other sweet foods nor did it vary among men who also smoked, were inactive or consumed a lot of alcohol. And, despite being strongly associated with greater intake of calories, chocolate lowered the overall risk of cardiovascular or any other disease by as much as 50 percent.
Although the chocolate definitely decreased blood pressure and prolonged life, the two were not statistically related, according to the researchers. This means that the exact mechanism by which chocolate helps remains a mystery. "Our findings, therefore, suggest that the lower cardiovascular mortality risk related with cocoa intake is mediated by mechanisms other than lowering blood pressure," the authors write in their report, published yesterday in the Archives of Internal Medicine. "Because cocoa is a rich source of antioxidants, it may also be related to other diseases that are linked to oxidative stress (e.g. pulmonary diseases, including chronic obstructive pulmonary disease and certain types of cancer)."