The Effect of Curcumin on Lipid Profile and Glycemic Status of Patients with Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Type 2 diabetes mellitus (T2DM) is a progressive metabolic disorder, some natural compounds are thought to be beneficial in improving the metabolic status of patients with T2DM. Curcumin is the main bioactive agent of turmeric, the impact of curcumin on T2DM is still controversial. This meta-analysis aimed to evaluate the effects of curcumin on lipids profile and glucose status in patients with T2DM. Randomized controlled trials (RCTs) examining the effects of curcumin on lipids profile and glycemic control of T2DM patients were searched in PubMed, Embase, Web of Science and Cochrane Library. Pooled estimates of weighted mean difference (WMD) were calculated between intervention and control groups using random-effects or fixed-effects model. Subgroup and sensitivity analyses were conducted to assess the effects. Nine eligible RCT with 604 subjects were included. The estimated pooled mean changes with curcumin were −18.97 mg/dL (95% CI: −36.47 to −1.47; P=0.03) for triglyceride (TG), −8.91 mg/dL (95% CI: −14.18 to −3.63, P=0.001) for total cholesterol (TC), -4.01 mg/dL (95% CI: -10.96 to 2.95, P=0.259) for low density lipoprotein cholesterol (LDL-c), 0.32 mg/dL (95% CI: −0.74 to 1.37, P=0.557) for high density lipoprotein cholesterol (HDL-c), −8.85 mg/dL (95% CI: −14.4 to −3.29, P=0.002) for fasting blood glucose (FBG), -0.54 (95% CI: −0.81 to −0.27, P ≤ 0.001) for glycated hemoglobin (HbA1c) (%) compared with controls. There was a significant heterogeneity for the influence of curcumin on TG, LDL-c, FBG and HbA1c. Subgroup analysis revealed that the heterogeneity mainly attributed to trial period, curcumin dosage and other therapy. The results of this study showed that curcumin supplementation had beneficial effects on glycemic status and some lipid parameters in patients with T2DM. Further studies with large-scale are still needed to confirm the results.