The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systematic Review.

Journal: Plant foods for human nutrition (Dordrecht, Netherlands)

Volume: 75

Issue: 1

Year of Publication: 2020

Affiliated Institutions:  Faculty of Health, University of Canberra, Canberra, ACT, , Australia. Nutrition & Health Substantiation Group, Nutrition and Health Program, Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Adelaide, SA, , Australia. Australian National University Medical School, Australian National University, Canberra, ACT, , Australia. Collaborative Research in Bioactives and Biomarkers (CRIBB) Group, University of Canberra, Bruce, ACT, , Australia. Faculty of Health, University of Canberra, Canberra, ACT, , Australia. nenad.naumovski@canberra.edu.au.

Abstract summary 

The green tea amino acid, L-theanine (L-THE) is associated with several health benefits, including improvements in mood, cognition and a reduction of stress and anxiety-like symptoms. This systematic review evaluated the effect of pure L-THE intake, in the form of orally administered nutritional supplements, on stress responses and anxiety levels in human randomised controlled trials. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist, 9 peer-reviewed journal articles were identified where L-THE as a supplement was compared to a control. Our findings suggest that supplementation of 200-400 mg/day of L-THE may assist in the reduction of stress and anxiety in people exposed to stressful conditions. Despite this finding, longer-term and larger cohort clinical studies, including those where L-THE is incorporated into the diet regularly, are needed to clinically justify the use of L-THE as a therapeutic agent to reduce stress and anxiety in people exposed to stressful conditions.

Authors & Co-authors:  Williams Jackson L JL Everett Julian M JM D'Cunha Nathan M NM Sergi Domenico D Georgousopoulou Ekavi N EN Keegan Richard J RJ McKune Andrew J AJ Mellor Duane D DD Anstice Nicola N Naumovski Nenad N

Study Outcome 

Source Link: Visit source

Statistics
Citations :  Neurochem Res. 1998 May;23(5):667-73
Authors :  10
Identifiers
Doi : 10.1007/s11130-019-00771-5
SSN : 1573-9104
Study Population
Male,Female
Mesh Terms
Amino Acids
Other Terms
Anxiety;Green tea;Human trials;L-theanine;Mental health;Stress response
Study Design
Cohort Study,Cross Sectional Study
Study Approach
Systemic Review
Country of Study
Publication Country
Netherlands