Effect of a polyphenol-rich diet on vascular function and other markers of cardiovascular risk
type: CreativeWork
description: Background Observational and intervention evidence to date indicates that polyphenol- rich foods, in particular berries and dark chocolate, may have the potential to influence cardiovascular disease risk. However, there are very few polyphenol-specific dietary intervention studies, and none of sufficiently robust design that assess the effect polyphenol-rich foods on vascular function tests of known prognostic significance and a range of cardiovascular endpoints in hypertensive patients. The study described in this thesis was based on the hypothesis that increasing overall polyphenol dietary intake, through increasing fruit and vegetable intake, and specifically including berries, and dark chocolate, would improve microvascular function and would also have a beneficial effect on platelet function, heart rate variability and other markers of cardiovascular risk in patients with hypertension. Methodology The study was a twelve-week randomised controlled, single blinded dietary intervention design. The study commenced with a four week run-in phase for all participants, during which they were asked to consume two portions or less of fruit and vegetables, excluding berries and dark chocolate. At the end of this period, subjects were randomised to continue with the low polyphenol diet for a further eight weeks or to consume a high polyphenol diet of six portions F&V (including one portion of berries per day) and 50g of dark chocolate per day. The primary endpoint was endothelium-dependent arterial vasodilator responses, assessed by venous occlusion plethysmography pre- and post-intervention. This is an invasive marker of microvascular function of known prognostic significance. Compliance was assessed with four-day food diaries and biochemical markers of nutritional status, including vitamin C, carotenoids and epicatechin. Other measures of cardiovascular risk included biochemical markers, such as lipid profile, hsCRP, PAI-1, 11-dehydrothromboxane B2 and heart rate variabi…
abstract: Background Observational and intervention evidence to date indicates that polyphenol- rich foods, in particular berries and dark chocolate, may have the potential to influence cardiovascular disease risk. However, there are very few polyphenol-specific dietary intervention studies, and none of sufficiently robust design that assess the effect polyphenol-rich foods on vascular function tests of known prognostic significance and a range of cardiovascular endpoints in hypertensive patients. The study described in this thesis was based on the hypothesis that increasing overall polyphenol dietary intake, through increasing fruit and vegetable intake, and specifically including berries, and dark chocolate, would improve microvascular function and would also have a beneficial effect on platelet function, heart rate variability and other markers of cardiovascular risk in patients with hypertension. Methodology The study was a twelve-week randomised controlled, single blinded dietary intervention design. The study commenced with a four week run-in phase for all participants, during which they were asked to consume two portions or less of fruit and vegetables, excluding berries and dark chocolate. At the end of this period, subjects were randomised to continue with the low polyphenol diet for a further eight weeks or to consume a high polyphenol diet of six portions F&V (including one portion of berries per day) and 50g of dark chocolate per day. The primary endpoint was endothelium-dependent arterial vasodilator responses, assessed by venous occlusion plethysmography pre- and post-intervention. This is an invasive marker of microvascular function of known prognostic significance. Compliance was assessed with four-day food diaries and biochemical markers of nutritional status, including vitamin C, carotenoids and epicatechin. Other measures of cardiovascular risk included biochemical markers, such as lipid profile, hsCRP, PAI-1, 11-dehydrothromboxane B2 and heart rate variabi…
author: Noad, Rebecca Louise
language: eng
date published: 2014-7
date modified: 2026-07-24T03:55:12Z
provider: Queen's University Belfast
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Queen's University Belfast