Moderate Weight Loss Decreases Oxidative Stress and Increases Antioxidant Status in Patients with Metabolic Syndrome

Background. Oxidative stress is enhanced in metabolic syndrome (MetS) and believed to contribute to accelerated atherosclerosis. Weight loss is associated with lowered oxidative stress. Methods. We performed a cross-sectional study in 92 consecutive patients with metabolic syndrome and 80 without. A dietary intervention with moderately low-calorie diet (600 calories/day negative energy balance) was carried out in 53 of metabolic syndrome patients. Oxidative stress, assessed by sNOX2-dp and urinary 8-iso-PGF2α, and antioxidant status, assessed by serum levels of vitamin E and adiponectin, were measured before and after 6 months. Results. Serum vitamin E/cholesterol ratio was significantly lower in metabolic syndrome compared to controls (P < 0.001) and decreased by increasing the number of metabolic syndrome components (P < 0.001). After six months, 23 and 30 patients showed >5% (group A) or <5% (group B) weight loss, respectively. Urinary 8-iso-PGF2α (−39.0%), serum sNOX2-dp (−22.2%), adiponectin (+125%), and vitamin E/cholesterol ratio (+129.8%) significantly changed only in A group. Changes in body weight and in serum adiponectin were independent predictors of vitamin E/cholesterol ratio variation. Conclusion. Our findings show that in metabolic syndrome moderate weight loss is associated with multiple health benefits including not only oxidative stress reduction but also enhancement of antioxidant status.