This journal is a review of the published literature on green tea and is an update of the 2020 edition we previously published. This includes the topic of COVID-19, which has been a particular infection all over the world since 2020. 　　　To provide an overview of the efficacy of green tea for the management of some diseases and conditions. A literature review was performed using the electronic database PubMed for studies published between January 2000 and April 2022. Mainly we retrieved articles scored as evidence level 1or 2according to Minds Manual for Guideline Development 2007, however, they did not follow Minds Manual for Guideline Developed 2017 and did not fill evidence level. Furthermore, we briefly described the recommended intake of green tea per day.・AcknowledgmentThis review does not provide recommendations for the efficacy of green tea in the clinical setting but provides a summary of evidence.・Author Disclosure StatementWe, members of the Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, were supported by the research funding provided by ITO EN, LTD.