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Supplementation of the Pure Flavonoids Epicatechin and Quercetin Affects Some Biomarkers of Endothelial Dysfunction and Inflammation in (Pre)Hypertensive Adults: A Randomized Double-Blind, Placebo-Controlled, Crossover Trial

Dower JI, Geleijnse JM, Gijsbers L, Schalkwijk C, Kromhout D, Hollman PC

The Journal of nutrition, 2015

162 citations

Abstract

BACKGROUND: Consumption of flavonoid-rich foods such as cocoa and tea may reduce cardiovascular disease risk. The flavonoids epicatechin (in cocoa and tea) and quercetin (in tea) probably play a role by reducing endothelial dysfunction and inflammation, 2 main determinants of atherosclerosis.

OBJECTIVE: We studied the effects of supplementation of pure epicatechin and quercetin on biomarkers of endothelial dysfunction and inflammation.

METHODS: Thirty-seven apparently healthy (pre)hypertensive men and women (40-80 y) participated in a randomized, double-blind, placebo-controlled crossover trial. Participants ingested (-)-epicatechin (100 mg/d), quercetin-3-glucoside (160 mg/d), or placebo capsules for a period of 4 wk, in random order. Plasma biomarkers of endothelial dysfunction and inflammation were measured at the start and end of each 4-wk intervention period. The differences in changes over time between the intervention and placebo periods (Δintervention - Δplacebo) were calculated and tested with a linear mixed model for repeated measures.

RESULTS: Epicatechin changed Δepicatechin - Δplacebo for soluble endothelial selectin (sE-selectin) by -7.7 ng/mL (95% CI: -14.5, -0.83; P = 0.03) but did not significantly change this difference (-0.30; 95% CI: -0.61, 0.01; P = 0.06) for the z score for endothelial dysfunction. Quercetin changed Δquercetin - Δplacebo for sE-selectin by -7.4 ng/mL (95% CI: -14.3, -0.56; P = 0.03), that for IL-1β by -0.23 pg/mL (95% CI: -0.40, -0.06;…

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Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design.

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