28/10/2004 - Researchers from Spain have discovered that polyphenols found in cocoa extract influence human cellular responses to oxidative stress.
Veronique No and colleagues at the University of Barcelona in Spain studied the impact of epicatechin and other polyphenols in cocoa extract on the human colon. Polyphenols are flavonoid compounds and they have antioxidant activity which may help the body's cells resist damage by free radicals, believed to play a role in reducing the risk of various chronic illnesses afflicting world populations such as heart disease and cancer.
"Treatment with epicatechin decreased the expression of 21 genes and unregulated 24 genes. Upon incubation with the cocoa polyphenolic extract, 24 genes were underexpressed and 28 were overexpressed," write the researchers in the October issue of the Journal of Nutrition.
Flavonoids found in chocolate include the flavanols, notably the main flavonoid epicatechin, and catechin, and polymers of these, the proanthocyanidins. Some epidemiological studies suggest that high intakes of flavonoids are associated with the maintenance of cardiovascular health, although other factors may also account for the results.
In vitro (test tube) and in vivo (in humans) studies have shown that cocoa flavonoids and certain chocolates may decrease low-density-lipoprotein (LDL) oxidation, may modulate platelet activation and could positively affect the balance between certain hormones, or eicosanoids. These actions can play a role in maintaining heart health.