Abstract

Key evidence suggests (-)-epicatechin (EC) is the active flavanol responsible for an improved vascular response (measured by flow-mediated dilation; FMD) seen after ingestion of flavanol-rich cocoa. It is hypothesised that EC metabolites are able to improve nitric oxide (NO) bioavailability in the vascular endothelium, either through activation of endothelial NO synthase (eNOS) and/ or inhibition NAPDPH oxidase. Most research in this area has focused on the effects of high-flavanol experimental foods (>1 mg/kg BW EC). Comparatively, milk chocolate contains a much lower level of EC (>10 mg per portion) that may infer a lesser vascular effect if assuming a linear dose-response, although the dose-dependency of EC is relatively unknown. Our previous study sought to investigate the vascular effect of 3 low-level doses of pure EC (0.1, 0.5 and 1 mg/kg BW). Vascular results have shown a significantly improved FMD response at 2 hours with 0.5 mg/kg BW dose. This ‘active’ dose will inform the current project.

This project aims to investigate the effect of a daily intake of (-)-epicatechin rich milk chocolate on vascular function in healthy males. A randomised, double-blind, controlled, crossover intervention using a EC-rich milk chocolate (40 mg EC per 10 g) and a control milk chocolate (<5 mg EC per 10 g) will take place over 6 weeks. Acute study days (Day 1 and Day 14 of both interventions) will measure FMD at various time-points (1, 2, 4, 6 hours) and human samples (plasma and urine) will also be collected for analysis of cardiovascular-related markers.