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1,154 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 …
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. It not only contributes to tea flavor but also possesses several health benefits. Compared with its sedative and calming activities, the immunomodulatory effects of L-theanine h …
L-theanine (N-ethyl-gamma-glutamine) is the main amino acid in tea leaves. It not only contributes to tea flavor but also poss …
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 …
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 …
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 …
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 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, cogni …
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. However, it has not revealed a clear evidence-based result yet regarding theanine …
The results of acute and chronic toxicity tests conducted on the safety of theanine express that L-theanine is reliable …
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.
Tea (Camellia sinensis L.) is a very popular health drink and has attracted increasing attention in recent years due to its various bioactive substances. Among them, L-theanine, a unique free amino acid, is one of the most important substances in tea and endows tea …
Tea (Camellia sinensis L.) is a very popular health drink and has attracted increasing attention in recent years due to its various bioactiv …
1,154 results