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Year Number of Results
1992 1
1998 1
2003 1
2004 2
2005 2
2006 6
2007 8
2008 13
2009 7
2010 7
2011 13
2012 18
2013 9
2014 16
2015 13
2016 18
2017 34
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2023 63
2024 40

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444 results

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Page 1
L-Theanine and Immunity: A Review.
Chen S, Kang J, Zhu H, Wang K, Han Z, Wang L, Liu J, Wu Y, He P, Tu Y, Li B. Chen S, et al. Molecules. 2023 May 1;28(9):3846. doi: 10.3390/molecules28093846. Molecules. 2023. PMID: 37175254 Free PMC article. Review.
L-theanine (N-ethyl-gamma-glutamine) is the main amino acid in tea leaves. ...Compared with its sedative and calming activities, the immunomodulatory effects of L-theanine have received less attention. Clinical and epidemiological studies have shown th
L-theanine (N-ethyl-gamma-glutamine) is the main amino acid in tea leaves. ...Compared with its sedative and calming activitie
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 …
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.
Tea is known to be a rich source of flavonoid antioxidants. However tea also contains a unique amino acid, L-theanine that may modulate aspects of brain function in humans. ...These data indicate that L-theanine, at realistic dietary levels, has a sign …
Tea is known to be a rich source of flavonoid antioxidants. However tea also contains a unique amino acid, L-theanine that may …
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 cognitive functions, verbal fluency and executive function scores improved after L-theanine administration (p = 0.001 and 0.031, respectively). ...Our findings suggest that L-theanine has the potential to promote mental health in the general popula …
For cognitive functions, verbal fluency and executive function scores improved after L-theanine administration (p = 0.001 and …
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 …
L-theanine, unique amino acid of tea, and its metabolism, health effects, and safety.
Türközü D, Şanlier N. Türközü D, et al. Crit Rev Food Sci Nutr. 2017 May 24;57(8):1681-1687. doi: 10.1080/10408398.2015.1016141. Crit Rev Food Sci Nutr. 2017. PMID: 26192072 Review.
The results of acute and chronic toxicity tests conducted on the safety of theanine express that L-theanine is reliable in general even if it is consumed too much with diet. ...
The results of acute and chronic toxicity tests conducted on the safety of theanine express that L-theanine is reliable in gen …
L-Theanine: A Unique Functional Amino Acid in Tea (Camellia sinensis L.) With Multiple Health Benefits and Food Applications.
Li MY, Liu HY, Wu DT, Kenaan A, Geng F, Li HB, Gunaratne A, Li H, Gan RY. Li MY, et al. Front Nutr. 2022 Apr 4;9:853846. doi: 10.3389/fnut.2022.853846. eCollection 2022. Front Nutr. 2022. PMID: 35445053 Free PMC article. Review.
Due to the unique characteristics and beneficial functions, L-theanine has potential applications in the development of functional foods. This review summarized the influencing factors of L-theanine content in teas, the main health benefits and related …
Due to the unique characteristics and beneficial functions, L-theanine has potential applications in the development of functi …
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 …
A Novel Theanine Complex, Mg-L-Theanine Improves Sleep Quality via Regulating Brain Electrochemical Activity.
Dasdelen MF, Er S, Kaplan B, Celik S, Beker MC, Orhan C, Tuzcu M, Sahin N, Mamedova H, Sylla S, Komorowski J, Ojalvo SP, Sahin K, Kilic E. Dasdelen MF, et al. Front Nutr. 2022 Apr 5;9:874254. doi: 10.3389/fnut.2022.874254. eCollection 2022. Front Nutr. 2022. PMID: 35449538 Free PMC article.
L-Theanine is commonly used to improve sleep quality through inhibitory neurotransmitters. ...Using the caffeine-induced brain electrical activity model, here we investigated the potency of L-theanine and two novel Mg-L-theanine compounds
L-Theanine is commonly used to improve sleep quality through inhibitory neurotransmitters. ...Using the caffeine-induced brain
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
444 results