Introduction

Chocolate and cocoa contain a high level of flavonoids, specifically epicatechin, which may have beneficial cardiovascular effects on health. The ingestion of flavonol-rich cocoa is associated with acute elevation of circulating nitric oxide, enhanced flow-mediated vasodilation, and augmented microcirculation.

Prolonged intake of flavonol-rich cocoa has been linked to cardiovascular health benefits, though it should be noted that this refers to plain cocoa and dark chocolate. Milk chocolate's addition of whole milk reduces the overall cocoa content per ounce while increasing saturated fat levels, possibly negating some of cocoa's heart-healthy potential benefits. Nevertheless, studies have still found short term benefits in LDL cholesterol levels from dark chocolate consumption.

Hollenberg and colleagues of Harvard Medical School studied the effects of cocoa and flavanols on Panama's Kuna Indian population, who are heavy consumers of cocoa. The researchers found that the Kuna Indians living on the islands had significantly lower rates of heart disease and cancer compared to those on the mainland who do not drink cocoa as on the islands. It is believed that the improved blood flow after consumption of flavanol-rich cocoa may help to achieve health benefits in hearts and other organs. In particular, the benefits may extend to the brain and have important implications for learning and memory.
Foods rich in cocoa appear to reduce blood pressure but drinking green and black tea may not, according to an analysis of previously published research in the April 9, 2007 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.