Can Chocolate Prevent Strokes?

Can Chocolate Prevent Strokes? Research that suggests chocolate and cocoa powder may lower blood pressure (BP) has been accumulating for many years. This research began with observations of the Kuna Indians of Panama, who see little or no rise in BP with age. The Kuna living on their island homes drink 5 or more cups of a cocoa drink. The Kuna who live in Panama City, on the other hand, do not, and they see their BP rise with age, just like others in Panama. Cocoa beans, like many other plant foods, contain phytochemicals that appear to improve the functioning of the endothelial cells that line the lumen of arteries. These and similar phytochemicals called flavanols are also found in tea, the skin of grapes, and numerous other plant foods. Chocolate flavanols have been shown to help dilate blood vessels, improve blood flow to the brain and heart, and help lower blood pressure. There is also limited evidence that chocolate flavanols may help reduce platelet adhesion and improve insulin sensitivity. Much of this research has been short-term and used specially processed cocoa powder processed in ways that do not drastically reduce flavanol content.The problem with flavanols is that they are bitter, so most cocoa is processed with alkali (called “dutching”) to eliminate them. Dutching also darkens the cocoa powder so buying “dark” chocolate usually results in a low flavanol content chocolate. Also, many chocolate products are high in sugar and have added milk fat. Would the small amounts of chocolate flavanols in modern diets still reduce the risk of cardiovascular disease [Hollenberg NK. Circulation 2007;116:2360-2]?New research from Sweden found that consuming chocolate was associated with a significant reduction in the risk of experiencing a stroke. Unlike many observational studies, this was a prospective study with a fairly long-term follow-up. Researchers from the Karolinska Institute in Stockholm followed over 37,000 men for an average of ten years. At the study’s onset, the men filled out a questionnaire regarding their health and also completed a food frequency questionnaire (FFQ). The FFQ results were used to estimate each man’s weekly chocolate consumption. This data on chocolate intake was then correlated with data from the Swedish Hospital Discharge Registry that looked at the incidence of stroke in these men over the ensuing 10 years. Men in the highest quartile of chocolate consumption had a 17 percent lower risk of stroke than the 25% consuming the least chocolate. However, this effect disappeared among men with a history of high blood pressure. Given that elevated BP is the #1 risk factor for stroke and chocolate flavanols help lower BP, this is perhaps not surprising.Bottom Line:Most of the chocolate consumed in the USA is alkali processed and much of it has a lot of butterfat and refined sugar added to it. For now, the best bet for getting more healthful flavanols in the diet is eating more minimally processed plant foods. Cocoa not processed with alkali with a bitter taste is far better than a milk chocolate candy bar. By James Kenney, PhD, FACN