Cocoa linked to improved cardiovascular health

18/01/06 While a growing number of studies has shown a link between flavanol-rich cocoa and cardiovascular health, scientists have now substantiated a causal relationship between specific compounds present in cocoa and cardiovascular health. Published in the Proceedings of the National Academy of Sciences of the United States of America (PNAS), this new study identifies the flavanol, (-)epicatechin, as one of the bioactive nutrients in cocoa that can improve the ability of blood vessels to relax.

An international team of scientists from the University of Dusseldorf, Germany; the University of California, Davis; Mars, Incorporated; and Harvard Medical School conducted a series of studies examining the role of specific cocoa flavanols in cardiovascular health.

In a randomized, double-blind, cross-over investigation, the researchers provided healthy male participants with a specially prepared cocoa drink that was either high or low in certain cocoa flavanols. Only the group consuming the flavanol-rich cocoa experienced increased blood vessel relaxation.  The researchers demonstrated that the relaxation response mediated by cocoa flavanols is dependent on nitric oxide, a key signal released by the inner lining of blood vessels (the endothelium) essential for normal blood vessel function and healthy blood flow.

To provide direct evidence for the specific flavanol in cocoa that is partly responsible for the circulatory benefits, the research team conducted a "proof-of-concept" study.  During this part of the investigation, participants drank either a placebo or a beverage containing isolated, cocoa-derived (-)epicatechin.  The researchers demonstrated that the group of participants receiving the (-)epicatechin had vessel relaxation and nitric oxide responses similar to those experienced following the consumption of the flavanol-rich cocoa drink.  Based on these findings, the investigators concluded that (-)epicatechin is one of the active nutrients in certain cocoas exerting the observed vascular benefits.

(-)Epicatechin, a nutrient that may be found in certain fruit and vegetables, green teas, red wine and purple grape juice, is especially abundant in certain cocoas.

To assess the potential long-term benefits of a flavanol-rich diet, the researchers studied two populations of Kuna Indians of Panama. Previous work by Dr. Norman Hollenberg has shown that hypertension is rare among the indigenous Kuna Indians living on the islands as compared to those living on the mainland.  The island-dwelling Kuna Indians traditionally consume large quantities of flavanol-rich cocoa (an average of 3-4 cups daily), while those who live in the suburbs of Panama City consume very little cocoa, supporting the idea that cocoa flavanols may be responsible for the lower blood pressure in the island dwellers.  Linking Dr. Hollenberg's observations to their own findings, Schroeter and colleagues found that the Kuna Indians on the island who regularly consume flavanol-rich cocoa had higher levels of flavanols, as well as higher levels of nitric oxide metabolites in their circulation compared to the mainland Indians who consume little cocoa.

In addition to collaborating on this research, Mars, Incorporated financially supported it and provided the flavanol-rich cocoa (Cocoapro cocoa powder) that was used throughout these investigations.

Cocoapro cocoa powder is used in Dove Dark Chocolate, as well as in the new heart-healthy snack CocoaVia.