Rebecca L Noad1, Ciara Rooney2, Damian McCall3, Ian S Young1, David McCance3, Michelle C McKinley4, Jayne V Woodside4, Pascal P McKeown1. 1. Centre for Public Health, Queen's University Belfast, Belfast, UK Cardiology Department, Belfast Health and Social Care Trust, Belfast, UK. 2. Centre for Public Health, Queen's University Belfast, Belfast, UK. 3. Cardiology Department, Belfast Health and Social Care Trust, Belfast, UK. 4. Centre for Public Health, Queen's University Belfast, Belfast, UK UKCRC Centre of Excellence for Public Health, Queen's University Belfast, Belfast, UK.
Abstract
OBJECTIVES: There is previous epidemiological evidence that intake of polyphenol-rich foods has been associated with reduced cardiovascular disease risk. We aimed to investigate the effect of increasing dietary polyphenol intake on microvascular function in hypertensive participants. METHODS: All participants completed a 4-week run-in phase, consuming <2 portions of fruit and vegetables (F&V) daily and avoiding berries and dark chocolate. Subjects were then randomised to continue with the low-polyphenol diet for 8 weeks or to consume a high-polyphenol diet of six portions F&V (including one portion of berries/day and 50 g of dark chocolate). Endothelium-dependent (acetylcholine, ACh) and endothelium-independent (sodium nitroprusside) vasodilator responses were assessed by venous occlusion plethysmography. Compliance with the intervention was measured using food diaries and biochemical markers. RESULTS: Final analysis of the primary endpoint was conducted on 92 participants. Between-group comparison of change in maximum % response to ACh revealed a significant improvement in the high-polyphenol group (p=0.02). There was a significantly larger increase in vitamin C, carotenoids and epicatechin in the high-polyphenol group (between-group difference p<0.001; p<0.001; p=0.008, respectively). CONCLUSIONS: This study has shown that increasing the polyphenol content of the diet via consumption of F&V, berries and dark chocolate results in a significant improvement in an established marker of cardiovascular risk in hypertensive participants. TRIAL REGISTRATION NUMBER: NCT01319786. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
OBJECTIVES: There is previous epidemiological evidence that intake of polyphenol-rich foods has been associated with reduced cardiovascular disease risk. We aimed to investigate the effect of increasing dietary polyphenol intake on microvascular function in hypertensive participants. METHODS: All participants completed a 4-week run-in phase, consuming <2 portions of fruit and vegetables (F&V) daily and avoiding berries and dark chocolate. Subjects were then randomised to continue with the low-polyphenol diet for 8 weeks or to consume a high-polyphenol diet of six portions F&V (including one portion of berries/day and 50 g of dark chocolate). Endothelium-dependent (acetylcholine, ACh) and endothelium-independent (sodium nitroprusside) vasodilator responses were assessed by venous occlusion plethysmography. Compliance with the intervention was measured using food diaries and biochemical markers. RESULTS: Final analysis of the primary endpoint was conducted on 92 participants. Between-group comparison of change in maximum % response to ACh revealed a significant improvement in the high-polyphenol group (p=0.02). There was a significantly larger increase in vitamin C, carotenoids and epicatechin in the high-polyphenol group (between-group difference p<0.001; p<0.001; p=0.008, respectively). CONCLUSIONS: This study has shown that increasing the polyphenol content of the diet via consumption of F&V, berries and dark chocolate results in a significant improvement in an established marker of cardiovascular risk in hypertensive participants. TRIAL REGISTRATION NUMBER: NCT01319786. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Authors: Maravillas Sánchez Macarro; Juan Pablo Martínez Rodríguez; Enrique Bernal Morell; Silvia Pérez-Piñero; Desirée Victoria-Montesinos; Ana María García-Muñoz; Fernando Cánovas García; Julián Castillo Sánchez; Francisco Javier López-Román Journal: Nutrients Date: 2020-05-19 Impact factor: 5.717