Effects of green tea supplementation on serum concentrations of adiponectin in patients with type 2 diabetes mellitus: a systematic review and meta-analysis

Context A decrease in adiponectin concentration is associated with obesity-related diseases such as insulin resistance, type 2 diabetes mellitus (T2DM), and cardiovascular disease (CVD). Objective We aimed to evaluate the effects of green tea supplementation on serum concentrations of adiponectin in patients with T2DM. Methods A systematic search was performed on the ISI Web of Science, PubMed, Embase and Scopus to find articles related to the effects of the green tea supplementation on adiponectin concentrations in T2DM patients, up to June 2019. Meta-analyses were performed using both the random and fixed effects model where appropriate. Results The initial search yielded 1010 publications. Data were pooled from five trials including 333 patients with T2DM. A meta-analysis of five RCTs demonstrated that green tea supplementation significantly increased adiponectin concentrations compared to control groups. Conclusion Our meta-analysis revealed that green tea supplementation increased adiponectin concentrations in patients with T2DM.