Anti-inflammatory and antioxidant effects of resveratrol in healthy smokers a randomized, double-blind, placebo-controlled, cross-over trial

OBJECTIVE: 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. METHODS AND RESULTS: 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. CONCLUSIONS: Because resveratrol has anti-inflammatory, anti-oxidant, and hypotriglyceridemic effects, its supplementation may beneficially affect the increased cardiovascular risk of healthy smokers.