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.