The effects of curcumin supplementation on body weight, body mass index and waist circumference: a systematic review and dose-response meta-analysis of randomized controlled trials

Abstract

Background & Objectives: Inconsistent data are available about the effect of curcumin supplementation on body weight. This systematic review and meta-analysis was done to summarize data from available clinical trials on the effect of curcumin supplementation on body weight, Body Mass Index (BMI), and Waist Circumference (WC). Methods: PubMed, SCOPUS, Cochrane Library and Google Scholar were searched to find relevant articles up to August 2018. The effect sizes were expressed as weighted mean difference (WMD) and 95 confidence intervals (CI). Between-study heterogeneity was assessed using I-2. Subgroup analysis was done to find possible sources of heterogeneity. Results: Totally, 11 studies that enrolled 876 subjects (53 women) were included. Combining effect sizes suggested a significant effect of curcumin administration on body weight (Weighed Mean Difference (WMD): -1.14 kg, 95 CI: -2.16, -0.12, P = 0.02) and BMI (WMD: -0.48 kg/m2, 95 CI: -0.78, -0.17, P = 0.002), respectively. However, no significant effect of curcumin supplementation on WC was found (WMD: -1.51 cm, 95 CI: -4.041, 1.003, P = 0.23). Based on subgroup analysis, we found that the effect of curcumin on WC was significant in studies that prescribed >= 1000mg/d curcumin (P <= 0.001), those with the intervention duration of -8 weeks (P <= 0.001), and those that was performed on overweight subjects (P <= 0.001). Conclusions: We found a significant effect of curcumin supplementation on body weight and BMI, but not on WC. However, the effect of curcumin on WC was significant in studies done on overweight subjects, used >= 1000mg/d curcumin, and >= 8 weeks of duration.