Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Mar;75(1):12-23.
doi: 10.1007/s11130-019-00771-5.

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

Affiliations

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

Jackson L Williams et al. Plant Foods Hum Nutr. .

Abstract

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.

Keywords: Anxiety; Green tea; Human trials; L-theanine; Mental health; Stress response.

Similar articles

See all similar articles

Cited by 1 article

References

    1. Neurochem Res. 1998 May;23(5):667-73 - PubMed
    1. Am Heart J. 2000 Oct;140(4 Suppl):77-83 - PubMed
    1. Int J Food Sci Nutr. 2012 Mar;63 Suppl 1:90-7 - PubMed
    1. Altern Med Rev. 2011 Dec;16(4):348-54 - PubMed
    1. Nutr Rev. 2014 Aug;72(8):507-22 - PubMed

Publication types

LinkOut - more resources

Feedback