SCOPE: The aim of this article is to conduct an umbrella review to study the strength and validity of associations between tea consumption and diverse health outcomes. METHODS AND RESULTS: Meta-analyses of observational studies examining associations between tea consumption and health outcomes in all human populations and settings are screened. The umbrella review identifies 96 meta-analyses with 40 unique health outcomes. Tea consumption shows greater benefits than harm to health in this review. Dose-response analyses of tea consumption indicates reduced risks of total mortality, cardiac death, coronary artery disease, stroke, and type 2 diabetes mellitus with increment of two to three cups per day. Beneficial associations are also found for several cancers, skeletal, cognitive, and maternal outcomes. Harmful associations are found for esophageal and gastric cancer when the temperature of intake is more than 55-60 °C. CONCLUSION: Tea consumption, except for very hot tea, seems generally safe at usual levels of intake, with summary estimates indicating the largest reduction for diverse health outcomes at two to three cups per day. Generally, tea consumption seems more beneficial than harmful in this umbrella review. Randomized controlled trials are further needed to understand whether the observed associations are causal.
SCOPE: The aim of this article is to conduct an umbrella review to study the strength and validity of associations between tea consumption and diverse health outcomes. METHODS AND RESULTS: Meta-analyses of observational studies examining associations between tea consumption and health outcomes in all human populations and settings are screened. The umbrella review identifies 96 meta-analyses with 40 unique health outcomes. Tea consumption shows greater benefits than harm to health in this review. Dose-response analyses of tea consumption indicates reduced risks of total mortality, cardiac death, coronary artery disease, stroke, and type 2 diabetes mellitus with increment of two to three cups per day. Beneficial associations are also found for several cancers, skeletal, cognitive, and maternal outcomes. Harmful associations are found for esophageal and gastric cancer when the temperature of intake is more than 55-60 °C. CONCLUSION: Tea consumption, except for very hot tea, seems generally safe at usual levels of intake, with summary estimates indicating the largest reduction for diverse health outcomes at two to three cups per day. Generally, tea consumption seems more beneficial than harmful in this umbrella review. Randomized controlled trials are further needed to understand whether the observed associations are causal.
Authors: Dena Zeraatkar; Arrti Bhasin; Rita E Morassut; Isabella Churchill; Arnav Gupta; Daeria O Lawson; Anna Miroshnychenko; Emily Sirotich; Komal Aryal; David Mikhail; Tauseef A Khan; Vanessa Ha; John L Sievenpiper; Steven E Hanna; Joseph Beyene; Russell J de Souza Journal: Am J Clin Nutr Date: 2021-06-01 Impact factor: 7.045
Authors: Gwang Hun Jeong; Giuseppe Grosso; Dagfinn Aune; Brendon Stubbs; Ai Koyanagi; Eunyoung Cho; Edward L Giovannucci; Jae I L Shin Journal: Adv Nutr Date: 2021-07-30 Impact factor: 11.567