Effects of alcohol and polyphenols from beer on atherosclerotic biomarkers in high cardiovascular risk men: A randomized feeding trial

Abstract

Background and aims. Moderate alcohol consumption exerts a cardioprotective effect, but no studies have evaluated the alcohol-independent cardiovascular effects of the non-alcoholic components of beer. We aimed to evaluate the effects of ethanol and the phenolic compounds of beer on classical and novel cardiovascular risk factors. Methods and results. Thirty-three high risk male volunteers were included in a randomized, crossover feeding trial. After a washout period, all subjects received beer (30 g alcohol/d, 660 mL), the equivalent amount of polyphenols as non-alcoholic beer (990 mL), and gin (30 g alcohol/d, 100 mL) for 4 weeks. All outcomes were evaluated before and after each intervention period. Moderate alcohol consumption increased serum HDL-cholesterol (∼5%), ApoA-I (∼6%), ApoA-II (∼7%) and adiponectin (∼7%), and decreased serum fibrinogen (∼8%), and interleukin (IL)-5 (∼14%) concentrations, whereas the non-alcoholic fraction of beer (mainly polyphenols) increased the receptor antagonist of IL-1 (∼24%), and decreased lymphocyte expression of lymphocyte function-associated antigen-1 (∼11%), lymphocyte and monocyte expression of Sialil-Lewis X (∼16%) and monocyte expression of CCR2 (∼31%), and tumor necrosis factor (TNF)-β (∼14%) and IL-15 (∼22%) plasma concentrations. No changes were observed in glucose metabolism parameters or in body weight and adiposity parameters. Conclusion. The phenolic content of beer reduces leukocyte adhesion molecules and inflammatory biomarkers, whereas alcohol mainly improves the lipid profile and reduces some plasma inflammatory biomarkers related to atherosclerosis. Trial registration number: ISRCTN95345245 (http://www.isrctn.org/).