The effects of curcumin supplementation on body mass index, body weight, and waist circumference in patients with nonalcoholic fatty liver disease: A systematic review and dose-response meta-analysis of randomized controlled trials

Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver-related morbidity; its prevalence is elevating due to the rising epidemic of obesity. Several clinical trials have examined the effects of curcumin supplementation on anthropometric variables in NAFLD patients with inconclusive results. This dose-response meta-analysis aimed to evaluate the impact of curcumin supplementation on body mass index (BMI), body weight, and waist circumference (WC) in patients with NAFLD. A systematic review of the literature was conducted using PubMed/Medline, ISI Web of Science, Scopus, Cochrane Library, EMBASE, Google Scholar, Sid.ir, and to identify eligible studies up to March 2019. A meta-analysis of eligible studies was performed using the random-effects model to estimate the pooled effect size. Eight randomized controlled trials with 520 participants (curcumin group = 265 and placebo group = 255) were included. Supplementation dose and duration ranged from 70 to 3,000 mg/day and 8 to 12 weeks, respectively. Curcumin supplementation significantly reduced BMI (weighted mean difference [WMD] = -0.34 kg/m(2), 95% CI [-0.64, -0.04], p < .05) and WC (WMD = -2.12 cm, 95% CI [-3.26, -0.98], p < .001). However, no significant effects of curcumin supplementation on body weight were found. These results suggest that curcumin supplementation might have a positive effect on visceral fat and abdominal obesity that have been associated with NAFLD.