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Year Number of Results
1992 1
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609 results

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Page 1
The Cognitive-Enhancing Outcomes of Caffeine and L-theanine: A Systematic Review.
Anas Sohail A, Ortiz F, Varghese T, Fabara SP, Batth AS, Sandesara DP, Sabir A, Khurana M, Datta S, Patel UK. Anas Sohail A, et al. Cureus. 2021 Dec 30;13(12):e20828. doi: 10.7759/cureus.20828. eCollection 2021 Dec. Cureus. 2021. PMID: 35111479 Free PMC article. Review.
The cognitive function of attention is also enhanced by the amino acid: L-theanine. The mechanism of action is that it behaves like a glutamate reuptake inhibitor while also acting in the hippocampus as a competitive low-affinity glutamate receptor antagonist. ...Ou …
The cognitive function of attention is also enhanced by the amino acid: L-theanine. The mechanism of action is that it behaves …
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 for sleep …
For stress-related symptoms, Self-rating Depression Scale, State-Trait Anxiety Inventory-trait, and Pittsburgh Sleep Quality Index (PSQI) sc …
L-theanine, a natural constituent in tea, and its effect on mental state.
Nobre AC, Rao A, Owen GN. Nobre AC, et al. Asia Pac J Clin Nutr. 2008;17 Suppl 1:167-8. Asia Pac J Clin Nutr. 2008. PMID: 18296328 Free article. Clinical Trial.
Trends in Food Science & Tech 1999;10;199-204). L-theanine significantly increases activity in the alpha frequency band which indicates that it relaxes the mind without inducing drowsiness. ...These data indicate that L-theanine, at realistic dieta …
Trends in Food Science & Tech 1999;10;199-204). L-theanine significantly increases activity in the alpha frequency band wh …
The combined effects of L-theanine and caffeine on cognitive performance and mood.
Owen GN, Parnell H, De Bruin EA, Rycroft JA. Owen GN, et al. Nutr Neurosci. 2008 Aug;11(4):193-8. doi: 10.1179/147683008X301513. Nutr Neurosci. 2008. PMID: 18681988 Clinical Trial.
The aim of this study was to compare 50 mg caffeine, with and without 100 mg L-theanine, on cognition and mood in healthy volunteers. The effects of these treatments on word recognition, rapid visual information processing, critical flicker fusion threshold, attenti …
The aim of this study was to compare 50 mg caffeine, with and without 100 mg L-theanine, on cognition and mood in healthy volu …
L-Theanine reduces psychological and physiological stress responses.
Kimura K, Ozeki M, Juneja LR, Ohira H. Kimura K, et al. Biol Psychol. 2007 Jan;74(1):39-45. doi: 10.1016/j.biopsycho.2006.06.006. Epub 2006 Aug 22. Biol Psychol. 2007. PMID: 16930802 Clinical Trial.
L-Theanine is an amino acid contained in green tea leaves which is known to block the binding of L-glutamic acid to glutamate receptors in the brain. ...Twelve participants underwent four separate trials: one in which they took L-Theanine at the start …
L-Theanine is an amino acid contained in green tea leaves which is known to block the binding of L-glutamic acid to glutamate …
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. ...
The green tea amino acid, L-theanine (L-THE) is associated with several health benefits, including improvements in mood …
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 …
The effects of L-theanine, caffeine and their combination on cognition and mood.
Haskell CF, Kennedy DO, Milne AL, Wesnes KA, Scholey AB. Haskell CF, et al. Biol Psychol. 2008 Feb;77(2):113-22. doi: 10.1016/j.biopsycho.2007.09.008. Epub 2007 Sep 26. Biol Psychol. 2008. PMID: 18006208 Clinical Trial.
L-Theanine increased 'headache' ratings and decreased correct serial seven subtractions. ...There was also a significant positive caffeine x L-theanine interaction on delayed word recognition reaction time. These results suggest that beverages containi …
L-Theanine increased 'headache' ratings and decreased correct serial seven subtractions. ...There was also a significant posit …
The effects of L-theanine consumption on sleep outcomes: A systematic review and meta-analysis.
Bulman A, D'Cunha NM, Marx W, Turner M, McKune A, Naumovski N. Bulman A, et al. Sleep Med Rev. 2025 Jun;81:102076. doi: 10.1016/j.smrv.2025.102076. Epub 2025 Feb 25. Sleep Med Rev. 2025. PMID: 40056718 Free article.
Randomised controlled trials investigating the effects of L-theanine supplementation on sleep quality in humans of all ages and health status were included. ...The findings indicate the potential use of L-theanine in the management of sleep disturbance …
Randomised controlled trials investigating the effects of L-theanine supplementation on sleep quality in humans of all ages an …
Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study.
Baba Y, Inagaki S, Nakagawa S, Kaneko T, Kobayashi M, Takihara T. Baba Y, et al. J Med Food. 2021 Apr;24(4):333-341. doi: 10.1089/jmf.2020.4803. Epub 2021 Mar 22. J Med Food. 2021. PMID: 33751906 Free PMC article. Clinical Trial.
l-theanine (gamma-glutamylethylamide), an amino acid in green tea, has been shown to affect brain functions by relieving stress disorders, improving mood, and maintaining normal sleep. ...In conclusion, our study indicated that l-theanine may contribut …
l-theanine (gamma-glutamylethylamide), an amino acid in green tea, has been shown to affect brain functions by relieving stres …
609 results