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The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systematic Review.
Williams JL, Everett JM, D'Cunha NM, Sergi D, Georgousopoulou EN, Keegan RJ, McKune AJ, Mellor DD, Anstice N, Naumovski N. Williams JL, et al. Plant Foods Hum Nutr. 2020 Mar;75(1):12-23. doi: 10.1007/s11130-019-00771-5. Plant Foods Hum Nutr. 2020. PMID: 31758301
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. ...Our findings suggest that supplementation of 200-400 mg/day of L- …
The green tea amino acid, L-theanine (L-THE) is associated with several health benefits, including improvements in mood …
Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial.
Hidese S, Ogawa S, Ota M, Ishida I, Yasukawa Z, Ozeki M, Kunugi H. Hidese S, et al. Nutrients. 2019 Oct 3;11(10):2362. doi: 10.3390/nu11102362. Nutrients. 2019. PMID: 31623400 Free PMC article. Clinical Trial.
For stress-related symptoms, Self-rating Depression Scale, State-Trait Anxiety Inventory-trait, and Pittsburgh Sleep Quality Index (PSQI) scores decreased after L-theanine administration (p = 0.019, 0.006, and 0.013, respectively). The PSQI subscale scores fo …
For stress-related symptoms, Self-rating Depression Scale, State-Trait Anxiety Inventory-trait, and Pittsburgh Sleep Quality Index (P …
GABA and l-theanine mixture decreases sleep latency and improves NREM sleep.
Kim S, Jo K, Hong KB, Han SH, Suh HJ. Kim S, et al. Pharm Biol. 2019 Dec;57(1):65-73. doi: 10.1080/13880209.2018.1557698. Pharm Biol. 2019. PMID: 30707852 Free PMC article.
The use of GABA/l-theanine mixture rather than GABA or l-theanine alone restored to normal levels sleep time and quality in the arousal animal model. ...CONCLUSIONS: GABA/l-theanine mixture has a positive synergistic effect on sleep quali …
The use of GABA/l-theanine mixture rather than GABA or l-theanine alone restored to normal levels sleep time and …
Use of Nutritional Supplements Based on L-Theanine and Vitamin B6 in Children with Tourette Syndrome, with Anxiety Disorders: A Pilot Study.
Rizzo R, Prato A, Scerbo M, Saia F, Barone R, Curatolo P. Rizzo R, et al. Nutrients. 2022 Feb 18;14(4):852. doi: 10.3390/nu14040852. Nutrients. 2022. PMID: 35215501 Free PMC article. Clinical Trial.
OBJECTIVE: To evaluate the effectiveness of supplementation of both L-Theanine and Vitamin B6 in reducing tics and co-occurring disorders in a sample of youth with chronic tic disorder (CTD) or Tourette syndrome with anxiety symptoms. ...CONCLUSIONS: Suppleme …
OBJECTIVE: To evaluate the effectiveness of supplementation of both L-Theanine and Vitamin B6 in reducing tics and co-occurrin …
Psychotropic effects of (L)-theanine and its clinical properties: From the management of anxiety and stress to a potential use in schizophrenia.
Lopes Sakamoto F, Metzker Pereira Ribeiro R, Amador Bueno A, Oliveira Santos H. Lopes Sakamoto F, et al. Pharmacol Res. 2019 Sep;147:104395. doi: 10.1016/j.phrs.2019.104395. Epub 2019 Aug 11. Pharmacol Res. 2019. PMID: 31412272 Review.
(L)-theanine is an amino acid naturally found in green tea (Camellia sinensis) and some other plant extracts, and recent clinical studies have proposed promising adjuvant effects of (L)-theanine for the negative impact of anxiety and psychologic …
(L)-theanine is an amino acid naturally found in green tea (Camellia sinensis) and some other plant extracts, and recent clini …
The effects of L-theanine supplementation on the outcomes of patients with mental disorders: a systematic review.
Moshfeghinia R, Sanaei E, Mostafavi S, Assadian K, Sanaei A, Ayano G. Moshfeghinia R, et al. BMC Psychiatry. 2024 Dec 4;24(1):886. doi: 10.1186/s12888-024-06285-y. BMC Psychiatry. 2024. PMID: 39633316 Free PMC article.
BACKGROUND: When utilized as an adjunct with antidepressants, antipsychotics, and other psychopharmacological drugs, certain amino acids, such as L-Theanine (LT), have shown potential effectiveness in enhancing the symptomatic outcomes of patients with mental disord …
BACKGROUND: When utilized as an adjunct with antidepressants, antipsychotics, and other psychopharmacological drugs, certain amino acids, su …
l-theanine: From tea leaf to trending supplement - does the science match the hype for brain health and relaxation?
Dashwood R, Visioli F. Dashwood R, et al. Nutr Res. 2025 Feb;134:39-48. doi: 10.1016/j.nutres.2024.12.008. Epub 2025 Jan 2. Nutr Res. 2025. PMID: 39854799 Free PMC article. Review.
This review surveys the chemistry, metabolism, and purported biological activities of l-theanine. It is well absorbed from the intestine and can cross the blood-brain barrier. Some studies suggest l-theanine may increase alpha waves in the brain associ …
This review surveys the chemistry, metabolism, and purported biological activities of l-theanine. It is well absorbed from the …
Green tea effects on cognition, mood and human brain function: A systematic review.
Mancini E, Beglinger C, Drewe J, Zanchi D, Lang UE, Borgwardt S. Mancini E, et al. Phytomedicine. 2017 Oct 15;34:26-37. doi: 10.1016/j.phymed.2017.07.008. Epub 2017 Jul 27. Phytomedicine. 2017. PMID: 28899506 Free article.
PURPOSE: To assess the current state of knowledge in the literature regarding the effects of green tea or green tea extracts, l-theanine and epigallocatechin gallate both components of green tea-on general neuropsychology, on the sub-category cognition and on brain …
PURPOSE: To assess the current state of knowledge in the literature regarding the effects of green tea or green tea extracts, l-th …
Safety and Efficacy of AlphaWave( ) L-Theanine Supplementation for 28 Days in Healthy Adults with Moderate Stress: A Randomized, Double-Blind, Placebo-Controlled Trial.
Moulin M, Crowley DC, Xiong L, Guthrie N, Lewis ED. Moulin M, et al. Neurol Ther. 2024 Aug;13(4):1135-1153. doi: 10.1007/s40120-024-00624-7. Epub 2024 May 17. Neurol Ther. 2024. PMID: 38758503 Free PMC article.
BACKGROUND: Prolonged periods of stress may lead to negative health consequences. AlphaWave( ) L-Theanine was safe and efficacious during an acute stress challenge. However, double-blind, placebo-controlled clinical trials investigating the longer term effects of …
BACKGROUND: Prolonged periods of stress may lead to negative health consequences. AlphaWave( ) L-Theanine was safe and efficac …
Medicinal herbs for the treatment of anxiety: A systematic review and network meta-analysis.
Zhang W, Yan Y, Wu Y, Yang H, Zhu P, Yan F, Zhao R, Tian P, Wang T, Fan Q, Su Z. Zhang W, et al. Pharmacol Res. 2022 May;179:106204. doi: 10.1016/j.phrs.2022.106204. Epub 2022 Apr 1. Pharmacol Res. 2022. PMID: 35378276
BACKGROUND: Anxiety disorder is a common psychiatric illness. Medicinal herbs have become a field of interest in the treatment of anxiety. ...There was insufficient evidence to confirm the effectiveness of Valerian (MD: 0.95, 95% CrI: -6.57 to 8.42) in standard-cont …
BACKGROUND: Anxiety disorder is a common psychiatric illness. Medicinal herbs have become a field of interest in the treatment of …
72 results