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137 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.
Adenosine receptors types A1 and A2a in the brain are inhibited by caffeine: a stimulant known to augment attention by increasing cholinergic and dopaminergic transmission. The cognitive function of attention is also enhanced by the amino acid: L-theanine. Th …
Adenosine receptors types A1 and A2a in the brain are inhibited by caffeine: a stimulant known to augment attention by increasing cholinergi …
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 is an amino acid found naturally in tea. Despite the common consumption of L-theanine, predominantly in combination with caffeine in the form of tea, only one study to date has examined the cognitive effects of this substance alone, a …
L-Theanine is an amino acid found naturally in tea. Despite the common consumption of L-theanine, predominantly …
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 …
For cognitive functions, verbal fluency and executive function scores improved after L-theanine administration (p = 0.0 …
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, …
The aim of this study was to compare 50 mg caffeine, with and without 100 mg L-theanine, on cognition and mood in healt …
Effects of Tea (Camellia sinensis) or its Bioactive Compounds l-Theanine or l-Theanine plus Caffeine on Cognition, Sleep, and Mood in Healthy Participants: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
Payne ER, Aceves-Martins M, Dubost J, Greyling A, de Roos B. Payne ER, et al. Nutr Rev. 2025 Oct 1;83(10):1873-1891. doi: 10.1093/nutrit/nuaf054. Nutr Rev. 2025. PMID: 40314930 Free PMC article.
OBJECTIVE: The aim of this study was to assess the effects of tea, theanine alone, or theanine plus caffeine on cognition, mood, and sleep outcomes, using data from randomized controlled trials (RCTs) in healthy participants. ...CONCLUSIONS: This meta-analysi …
OBJECTIVE: The aim of this study was to assess the effects of tea, theanine alone, or theanine plus caffeine on cognition …
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 …
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 …
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.
However, the cognitive functions for which theanine is effective are unclear. This study aimed to clarify which cognitive functions are positively affected by intake of l-theanine. ...Cognitrax was used as a test battery for cognitive fun …
However, the cognitive functions for which theanine is effective are unclear. This study aimed to clarify which cognitive …
Effects of L-theanine-caffeine combination on sustained attention and inhibitory control among children with ADHD: a proof-of-concept neuroimaging RCT.
Kahathuduwa CN, Wakefield S, West BD, Blume J, Dassanayake TL, Weerasinghe VS, Mastergeorge A. Kahathuduwa CN, et al. Sci Rep. 2020 Aug 4;10(1):13072. doi: 10.1038/s41598-020-70037-7. Sci Rep. 2020. PMID: 32753637 Free PMC article. Clinical Trial.
We examined the acute effects of L-theanine, caffeine and their combination on sustained attention, inhibitory control and overall cognition in boys with attention deficit hyperactivity disorder (ADHD). ...L-Theanine improved total cognition …
We examined the acute effects of L-theanine, caffeine and their combination on sustained attention, inhibitory control and ove …
The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness.
Giesbrecht T, Rycroft JA, Rowson MJ, De Bruin EA. Giesbrecht T, et al. Nutr Neurosci. 2010 Dec;13(6):283-90. doi: 10.1179/147683010X12611460764840. Nutr Neurosci. 2010. PMID: 21040626 Clinical Trial.
Cognitive performance, self-reported mood, blood pressure, and heart rate were measured before L-theanine and caffeine administration (i.e. at baseline) and 20 min and 70 min thereafter. ...There were no significant effects on other cognitive tasks, su …
Cognitive performance, self-reported mood, blood pressure, and heart rate were measured before L-theanine and caffeine …
137 results