Effects of Resveratrol on Metabolic Indicators in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis

Background and Aims. Previous studies on the effects of resveratrol on metabolic indicators reported contradictory findings, and these indicators have not been frequently studied in patients with type 2 diabetes. In this study, we aimed to examine the effects of resveratrol on metabolic indicators in a specific group of people with type 2 diabetes using the most recent literature. Methods. We used RevMan 5.4 and Stata 14.0 software to identify randomized controlled studies on the impact of resveratrol on metabolic indicators in patients with type 2 diabetes using relevant search terms and keywords such as "resveratrol " and "type 2 diabetes " in the China National Knowledge Infrastructure, PubMed, Cochrane, and Embase. Data were expressed as the weighted mean difference (WMD) and 95% confidence interval (CI). Results. This meta-analysis included 19 studies involving 1151 patients with type 2 diabetes, including 584 patients treated with resveratrol and 567 patients who received placebo. Compared with the control data, large doses of resveratrol (>= 1000 mg) reduced fasting blood glucose levels (WMD: -18.76 mg/dL, 95% CI: -23.43, -14.09; P < 0.00001). Additionally, resveratrol reduced systolic blood pressure (WMD: -7.97 mmHg, 95% CI: -10.63, -5.31; P < 0.00001) and diastolic blood pressure (WMD: -3.55 mmHg, 95% CI: -5.18, -1.93; P < 0.00001) in patients with type 2 diabetes but did not improve waist circumference (WMD: 0.05 cm, 95% CI: -1.77, 1.88; P=0.95), triglyceride levels (WMD: -4.49 mg/dL, 95% CI: -24.23, 15.25; P=0.66), or high-density lipoprotein cholesterol levels (WMD: -1.05 mg/dL, 95% CI: -2.44, 0.33; P=0.14) in patients with type 2 diabetes. Conclusion. This systematic review and meta-analysis updated the most recent literature and provided new evidence, proving that resveratrol treatment can reduce systolic blood pressure and diastolic blood pressure. High-dose resveratrol can reduce fasting blood glucose in patients with type 2 diabetes, although it has no effect on waist circumference, triglyceride, and high-density lipoprotein cholesterol.