The effect of curcumin supplementation on circulating adiponectin and leptin concentration in adults: A GRADE-assessed systematic review and meta-analysis of randomized controlled trials.

Curcumin is a phytocompound found in the root of turmeric, a common herbal ingredient in many Asian cuisines. The compound contains anti-inflammatory activity, which is mediated through an up-regulation of adiponectin and reduction of leptin. Results of randomized controlled trials (RCTs) have shown that the effects of curcumin on adipokines are conflicting. Therefore, the current systematic review and meta-analysis of RCTs were conducted with the aim of elucidating the role of curcumin supplementation on serum adiponectin and leptin. The search included PubMed, Embase, Cochrane Library, Scopus, Web of Science, and Google Scholar from inception to August 2023. For net changes in adipokines, standardized mean differences (SMDs) were calculated using random effects models. 13 RCTs with 14 treatment arms were eligible for inclusion in this meta-analysis. Curcumin supplementation was effective in increasing serum adiponectin ((SMD= 0.86, 95% CI: 0.33, 1.39, p<0.001; I 2 = 93.1%, p< 0.001), and reducing serum leptin ((SMD = -1.42, 95% CI: -2.29, -0.54; p < 0.001; I 2 = 94.7%, p < 0.001). In conclusion, curcumin supplementation significantly increased circulating adiponectin and decreased leptin levels in adults.