Effects of green tea supplementation on obesity indices and adipokines in adults: a grade-assessed systematic review and dose-response meta-analysis of randomised controlled trials

In this systematic review and meta-analysis, the impact of green tea supplementation on measurement/indices of adiposity was investigated. Using predefined keywords, online databases (PubMed, Scopus, Web of Science Core Collection, and Google Scholar) were searched for relevant studies, published from inception up to February 2024. Data were extracted and registered. Subgroup analyses and the investigation of linear and non-linear associations were carried out. Green tea supplementation reduced BW (WMD: −0.74 kg; 95% CI: −0.97, −0.51), BMI (WMD: −0.29 kg/m²; 95% CI: −0.38, −0.19), WC (WMD: −1.04 cm; 95% CI: −1.55, −0.53), BFP (WMD: −0.65%; 95% CI: −1.03, −0.27), and leptin (WMD: −0.92 ng/ml; 95% CI: −1.71, −0.14), but did not change adiponectin levels (WMD: 0.20 µg/ml; 95% CI: −0.17, 0.57). Supplementation with green tea seems to be effective in reducing excess adiposity.