This randomized, placebo-controlled study was conducted to investigate whether curcuminoids have beneficial effects on type 2 diabetic patients and to examine the possible mechanisms of action. Overweight/obese type 2 diabetic patients (BMI ≥ 24.0; fasting blood glucose ≥ 7.0 mmol/L or postprandial blood glucose ≥11.1 mmol/L) were randomly assigned to 300 mg/day curcuminoids or placebo for three months. Bodyweight, glycosylated hemoglobin A(1c) (HbA1c), serum fasting glucose, free fatty acids (FFA), lipids, and lipoprotein lipase (LPL) were determined. One hundred patients (curcuminoids, N = 50; placebo, N = 50) completed the trial. Curcuminoids supplementation significantly decreased fasting blood glucose (P < 0.01), HbA1c (P = 0.031), and insulin resistance index (homeostasis model of assessment – insulin resistance; HOMA-IR) (P < 0.01). Curcuminoids also led to a significant decrease in serum total FFA (P < 0.01), triglycerides (P = 0.018), and an increase in LPL activity (p < 0.01). The authors concluded that these findings suggest a glucose-lowering effect of curcuminoids in type 2 diabetes. This effect is partially due to a decrease in serum FFA, which may result from promoting fatty acid oxidation and utilization. Mol Nutr Food Res. 2012 Aug 29. PMID: 22930403
