The beneficial vascular effects of cacao flavanols: having your cake and eating it too

Abstract

A SIGNIFICANT NUMBER OF EPIDEMIOLOGICAL studies report on the apparent beneficial effects of chocolate (i.e., cocoa) consumption on cardiovascular health, including reductions in morbidity and mortality (1, 2, 4). However, these reports are mostly of retrospective nature and do not demonstrate causality. Thus the need to implement well-designed prospective studies that unequivocally demonstrate a link between chocolate consumption and beneficial cardiovascular effects. These studies would need to take into account the variable and complex nature of cocoa product composition, since many of its constituents are known to have cardiovascular effects. Optimal trial design would test products with a defined composition that vary only the concentration of suspect bioactive molecules.In this issue of the Journal of Applied Physiology, Monahan et al. (3) report on the results of a randomized, double-blind, placebo-controlled study indicating that acute cocoa ingestion dose dependently increases brachial artery flow-mediated dilation in healthy older adults. It is well known that in older individuals vascular reactivity is diminished partly due to endothelial dysfunction. Thus approaches that can restore normal endothelial reactivity if sustained over time, are likely to translate into improved cardiovascular health. The population studied (23 subjects) were of an average age of 63 yr and normotensive. The study utilized five different formulations of a low-calorie (ϳ100 kcal) cocoa beverage, where most of the constituents (except total polyphenol, flavan 3-ols, and procyanidins content) were held constant. As polyphenol content increased (from 330 to 1,470 mg), the concentration of suspect bioactive molecules (the flavanols catechin and epicatechin) also increased. Concentrations varied from 0 to 48 mg of catechin and 0 to 96 mg of epicatechin. In a random and blinded manner, all of the subjects were provided each of the five different formulations, thus generating responses that should be internally consistent. Beverages were only given once, thus the responses generated were of acute nature.

Flavonoids, Proanthocyanidins, Vitamin C, and Antioxidant Activity of Theobroma grandiflorum (Cupuassu) Pulp and Seeds

“…It is well-known that cocoa seeds, cocoa powder, and liquor contain a wide range of monomeric flavan-3-ols and their oligomeric derivatives, called proanthocyanidins. Those flavonoids are associated with potential health benefits like antioxidant, anticancer, and anti-inflammatory activities, cardiovascular protective properties, modulation of immune response, endothelial function, and antimicrobial and enzyme inhibitory activities. − One activity reported is related to lipoxygenase inhibition by flavan-3-ols, which prevents oxidative cell damage by diminishing lipid peroxidation catalysis …”