Effects of Cocoa Procyanidins on Vascular Function

There is a question regarding the role of higher flavanol oligomers (procyanidins) and of intestinal flavanol metabolites i.e. valerolactones, in the context of flavanol intake-related vascular effects. Only flavanol monomers, and to a certain degree dimers, are absorbed in the small intestine and enter circulation. Higher oligomers (procyanidins) are not absorbed and are catabolized by the colonic microflora. The catabolites enter the circulation. Phenolic acids and valerolactones represent a significant proportion of these catabolites, reaching peak concentrations in the order of 6-10 h post ingestion. The vascular effects of these colonic microbiome-derived flavanol derivatives have not been studied so far. The purpose of the study is to determine the timecourse of endothelial function along with flavanol catabolites \& metabolites during acute, sustained, and acute on sustained ingestion of procyanidins as compared to previously used flavanol interventions, and flavanol free control.