The effects of supplementation with green tea on energy expenditure rate and thermal energy expenditure in adult individuals: A systematic review of clinical trials

Abstract As there is no systematic review on the effects of green tea on energy expenditure (EE) and thermal energy expenditure (TEE), the authors aimed to systematically examine whether green tea can affect EE and TEE in adult subjects. Five electronic databases including PubMed/Medline, Scopus, Web of Science, Embase and Cochrane library plus three Chinese databases were searched from 30th Jun 2019 to 1st January 2000 to find eligible clinical trials. Of 1016 publications, 6 clinical trials were included. In most studies, changes in EE following the consumption of green tea were not significant. However, fat oxidation increased in some studies after the intervention. No serious side effects were reported in any of the clinical trials following the supplementation with green tea. Green tea may increase EE and fat oxidation in adult individuals. However, the benefits of green tea for energy expenditure-related parameters including heart rate, carbohydrate oxidation, TEE, and RQ remain uncertain. Further clinical trials are needed to confirm the effects of green tea on EE and related parameters.