RESUMO
AIM: This study evaluated the effect of resveratrol administration on metabolic syndrome, insulin sensitivity, and insulin secretion. METHODS: A randomized, double-blind, placebo-controlled clinical trial was carried out in 24 patients with diagnosis of metabolic syndrome in accordance with the International Diabetes Federation criteria. Glucose and insulin levels were measured after a 75-gram dextrose load. Triglycerides and high-density lipoprotein cholesterol concentrations at baseline were also evaluated. Twelve patients received trans-resveratrol (500 mg) three times per day before meals for 90 days. The remaining 12 patients received placebo at the same dose. The area under the curve (AUC) values of glucose and insulin, total insulin secretion, first-phase of insulin secretion, and insulin sensitivity were calculated. RESULTS: After resveratrol administration, there were significant differences in total weight (94.4±13.2 vs. 90.5±12.3 kg, P=0.007), body mass index (BMI) (35.6±3.2 vs. 34.3±3.0 kg/m(2), P=0.006), fat mass (41.2±7.9 vs. 38.8±6.0 kg, P=0.001), and waist circumference (WC) (109±9 vs. 105±10 cm, P=0.004). There were also significant differences in AUC of insulin (48,418±22,707 vs. 26,473±8,273 pmol/L, P=0.003) and insulinogenic index (0.48±0.22 vs. 0.28±0.08, P=0.004). CONCLUSIONS: Administration of resveratrol significantly decreases weight, BMI, fat mass, WC, AUC of insulin, and total insulin secretion.