Anti-Inflammatory and Antioxidant Effects of Resveratrol in Healthy Smokers A Randomized, Double-Blind, Placebo-Controlled, Cross-Over Trial

Abstract

Smokers are characterized by a low-grade systemic inflammatory state and an oxidant-antioxidant imbalance. Few human studies were conducted on the effects of resveratrol, a natural compound with anti-inflammatory and antioxidant properties, and no trial on smokers has been performed to date. We evaluated whether resveratrol has beneficial effects on markers of inflammation and oxidative stress in smokers. A randomized, double- blind, cross-over trial was performed in 50 healthy adult smokers: 25 were randomly allocated to "resveratrol-first" (30-days: 500mg resveratrol/day, 30-days wash-out, 30-days placebo) and 25 to "placebo-first" (30-days placebo, 30-days wash-out, 30-days 500mg resveratrol/day). Resveratrol significantly reduced C-reactive protein (CRP) and triglyceride concentrations, and increased Total Antioxidant Status (TAS) values. After analyzing data with general linear models to assess period and carry-over effects, the ratios of the values after resveratrol to those after placebo were respectively: 0.47 (95%CI 0.38-0.59) -CRP- and 0.71 (95%CI 0.65-0.78) -triglycerides-, while TAS increased by 74.2 μmol/L (95%CI 60.8-87.6). Uric acid, glucose, insulin, cholesterol, liver enzyme concentrations, and weight, waist circumference, and blood pressure values did not significantly change after resveratrol supplementation. Because resveratrol has anti-inflammatory, anti-oxidant, and hypotriglyceridemic effects, its supplementation may beneficially affect the increased cardiovascular risk of healthy smokers.