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Review Article | Open Access

How does the tea L-theanine buffer stress and anxiety

Liwen WangaMargaret BrennanbShiming Lic( )Hui ZhaodKlaus W. LangeeCharles Brennanb,f( )
College of Food Science and Technology, Hebei Agricultural University, Baoding 071001, China
Department of Wine, Food and Molecular Biosciences, Lincoln University, Christchurch 7647, New Zealand
Hubei Key Laboratory of EFGIR, Huanggang Normal University, Huanggang 438000, China
Tianjin Key Laboratory of Food and Biotechnology, University of Commerce, Tianjin 300134, China
Department of Experimental Psychology, University of Regensburg, Regensburg 93040, Germany
School of Science, RMIT, Melbourne, VIC 3000, Australia

Peer review under responsibility of KeAi Communications Co., Ltd.

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Tea (Camellia sinensis) is widely considered to promote feelings of calming and soothing. This effect is attributed to L-theanine (L-γ-glutamylethylamide) in tea, a non-protein amino acid mainly derived from tea leaves. As a naturally occurring structural analogue of glutamate, L-theanine competes for the receptors with glutamate and is able to pass the blood-brain barrier to exert its relaxation effect. This review focuses on the relaxation effect of L-theanine, including animal models and the latest human trials as well as the potential molecular mechanisms regarding neuron stem cells. The biological efficacy of dietary L-theanine in the food matrix has been further discussed in this review in relation to the physiological changes in the gastrointestinal tract and bindings of L-theanine with other food components.



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Food Science and Human Wellness
Pages 467-475
Cite this article:
Wang L, Brennan M, Li S, et al. How does the tea L-theanine buffer stress and anxiety. Food Science and Human Wellness, 2022, 11(3): 467-475.








Web of Science






Received: 15 January 2021
Revised: 14 February 2021
Accepted: 07 March 2021
Published: 04 February 2022
© 2022 Beijing Academy of Food Sciences.

This is an open access article under the CC BY-NC-ND license (