INS and Insulin resistance: Curcumin/turmeric supplementation significantly reduced fasting blood glucose (FBG) (WMD = -10.15 mg/dL; 95% CI: -12.59, -7.72), hemoglobin A1c (HbA1c) (WMD = -0.32%; 95% CI: -0.43, -0.21), fasting insulin (WMD = -0.69 μU/ml; 95% CI: -1.27, -0.12), homeostatic model assessment of insulin resistance (HOMA-IR) (WMD = -0.46; 95% CI: -0.60, -0.32), and oral glucose tolerance test (OGTT) (WMD = -11.53 mg/dL; 95% CI: -22.68, -0.44) compared to control groups.