Turmeric Supplementation Improves Serum Glucose Indices and Leptin Levels in Patients with Nonalcoholic Fatty Liver Diseases

Objective: Insulin and leptin resistance are important risk factors for non-alcoholic fatty liver disease (NAFLD). There is limited evidence regarding the effects of turmeric on NAFLD. The aim of this study was to investigate the effects of turmeric supplementation on glycemic status and serum leptin levels in patients with NAFLD. Methods: This double-blind randomized controlled clinical trial was conducted on 46 patients with NAFLD (21males and 25 females) aged 20–60 years old and body mass index (BMI) between 24.9 and 40 kg/m2. The turmeric group (n = 23) was given six turmeric capsules daily for 12 weeks. Each capsule contained 500 mg turmeric powder (6×500 mg). The placebo group (n = 23) was given six placebo capsules daily for the same period. Fasting blood samples, anthropometric measurements, and physical activity levels were collected at the baseline and at the end of the study. Daily dietary intakes also were obtained throughout the study. Data were analyzed by independent t test, paired t test and analysis of covariance. Results: Turmeric consumption decreased serum levels of glucose, insulin, HOMA-IR and leptin (by 1.22, 17.69, 19.48 and 21.33% respectively, p < 0.05 for all) over 12 weeks compared with those variables in the placebo group. Changes in weight, BMI and liver enzymes were not significant compared to the placebo group. Conclusions: Turmeric supplementation improved glucose indexes and serum leptin levels and may be useful in the control of NAFLD complications.