The media are suddenly abuzz with the latest on the putative health benefits of one of our favorite foods: a study just published in BMJ reports that chocolate may improve cardiovascular health. Yet the study itself, as well as the exuberant news coverage, doesn t amount to much more than wishful thinking.
The study, a review of seven earlier studies comprising over 114,000 people, looked at the link between eating chocolate and a reduction in heart disease. Researchers from England and Colombia found that, in five of the seven studies (which amount to only 15,000 of the 114,000 subjects) there was an association between higher levels of chocolate consumption and lowered risk of cardiometabolic illness (heart disease, stroke, diabetes, and metabolic syndrome). The highest levels of consumption were correlated with a 37 percent drop in cardiovascular disease and a 29 percent reduction in stroke. The researchers suggest that a type of antioxidant called polyphenols, found in cocoa, could improve endothelial function, which may affect the risk of stroke and heart attack, as well as insulin resistance and blood pressure.
However, the researchers found no dose-response relationship between chocolate and the risk of the various disorders. This," says ACSH s Dr. Ruth Kava, is a major indication of the study s lack of credibility. If there is no correspondence between the amount of chocolate consumed and the associated benefits, it s hard to claim that there s a causal relationship.
ACSH's Dr. Gilbert Ross, after taking a look at the study, was not impressed. This sad excuse for a study is replete with unjustified corrections used as excuses for data-dredging, he says. While the authors state that five of the seven studies found a link between more chocolate and lower cardiometabolic disease, one wonders about the other two studies, which apparently contained over 85 percent of the total patients. He also notes that the studies assessed had a grab bag of different, non-standardized criteria, which is a common problem with meta-analysis. "In sum, says Dr. Ross, this study exemplifies the highly technical term GIGO : Garbage In, Garbage Out. Which is too bad, because we too wish we could eat chocolate as if it were as healthful as regular exercise. But that s just not the case.
Eat chocolate because you like it, not for health!
The media are suddenly abuzz with the latest on the putative health benefits of one of our favorite foods: a study just published in BMJ reports that chocolate may improve cardiovascular health.