TY - JOUR
T1 - The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels
T2 - a Systematic Review
AU - Williams, Jackson L.
AU - Everett, Julian M.
AU - D’Cunha, Nathan M.
AU - Sergi, Domenico
AU - Georgousopoulou, Ekavi N.
AU - Keegan, Richard J.
AU - McKune, Andrew J.
AU - Mellor, Duane D.
AU - Anstice, Nicola
AU - Naumovski, Nenad
N1 - © Springer Nature B.V. 2019. The final publication is available at Springer via http://dx.doi.org/10.1007/s11130-019-00771-5
PY - 2020/3
Y1 - 2020/3
N2 - 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.
AB - 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.
KW - Anxiety
KW - Green tea
KW - Human trials
KW - L-theanine
KW - Mental health
KW - Stress response
UR - http://www.scopus.com/inward/record.url?scp=85075370144&partnerID=8YFLogxK
UR - https://link.springer.com/article/10.1007%2Fs11130-019-00771-5
U2 - 10.1007/s11130-019-00771-5
DO - 10.1007/s11130-019-00771-5
M3 - Review article
AN - SCOPUS:85075370144
SN - 0921-9668
VL - 75
SP - 12
EP - 23
JO - Plant Foods for Human Nutrition
JF - Plant Foods for Human Nutrition
ER -