Pôsobí na: náladu

L-theanín (L-teanín) je jedným z hlavných aktívnych zložiek zeleného čaju (spolu s kofeínom a katechínmi). Podporuje uvoľnenie bez ospalosti, čo ho robí synergickým s kofeínom.


L-theanín sa zvyčajne užíva v dávke 100-200 mg, často spolu s kofeínom.

Medicínske upozornenie!


  1. Yamada T, et al. Theanine, r-glutamylethylamide, increases neurotransmission concentrations and neurotrophin mRNA levels in the brain during lactationLife Sci. (2007)
  2. Differences in free amino acids and total nitrogen contents among various prices of green tea.
  3. Comparison of Azorean tea theanine to teas from other origins by HPLC/DAD/FD. Effects of fermentation, drying temperature, drying time, and shoot maturity.
  4. Nobre AC, Rao A, Owen GN. L-theanine, a natural constituent in tea, and its effect on mental stateAsia Pac J Clin Nutr. (2008)
  5. L-theanine—a unique amino acid of green tea and its relaxation effect in humans.
  6. CASIMIR J, JADOT J, RENARD M. Separation and characterization of N-ethyl-gamma-glutamine from Xerocomus badiusBiochim Biophys Acta. (1960)
  7. Başkan MH, Aydın M. Electron paramagnetic resonance studies of gamma-irradiated dl-alanine ethyl ester hydrochloride, l-theanine and l-glutamic acid dimethyl ester hydrochlorideSpectrochim Acta A Mol Biomol Spectrosc. (2013)
  8. 200 mg of Zen: L-Theanine Boosts Alpha Waves, Promotes Alert Relaxation.
  9. Narukawa M, et al. Nerve and behavioral responses of mice to various umami substancesBiosci Biotechnol Biochem. (2011)
  10. Narukawa M, Morita K, Hayashi Y. L-theanine elicits an umami taste with inosine 5′-monophosphateBiosci Biotechnol Biochem. (2008)
  11. Lyon MR, Kapoor MP, Juneja LR. The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trialAltern Med Rev. (2011)
  12. Suntheanine: A pure and safe L-theanine dietary supplement for relaxation and stress relief.
  13. Process for producing theanine WO 2004016798 A1.
  14. Kimura K, et al. L-Theanine reduces psychological and physiological stress responsesBiol Psychol. (2007)
  15. Lu K, et al. The acute effects of L-theanine in comparison with alprazolam on anticipatory anxiety in humansHum Psychopharmacol. (2004)
  16. Gomez-Ramirez M, et al. The effects of L-theanine on alpha-band oscillatory brain activity during a visuo-spatial attention taskBrain Topogr. (2009)
  17. Park SK, et al. A combination of green tea extract and l-theanine improves memory and attention in subjects with mild cognitive impairment: a double-blind placebo-controlled studyJ Med Food. (2011)
  18. Tsuge H, et al. Theanine, gamma-glutamylethylamide, is metabolized by renal phosphate-independent glutaminaseBiochim Biophys Acta. (2003)
  19. Zarse K, Jabin S, Ristow M. L-Theanine extends lifespan of adult Caenorhabditis elegansEur J Nutr. (2012)
  20. Kimura R, Murata T. Influence of alkylamides of glutamic acid and related compounds on the central nervous system. I. Central depressant effect of theanineChem Pharm Bull (Tokyo). (1971)
  21. Terashima T, Takido J, Yokogoshi H. Time-dependent changes of amino acids in the serum, liver, brain and urine of rats administered with theanineBiosci Biotechnol Biochem. (1999)
  22. Yokogoshi H, et al. Effect of theanine, r-glutamylethylamide, on brain monoamines and striatal dopamine release in conscious ratsNeurochem Res. (1998)
  23. Christensen HN. Developments in amino acid transport, illustrated for the blood-brain barrierBiochem Pharmacol. (1979)
  24. Tamano H, et al. Preventive effect of theanine intake on stress-induced impairments of hippocamapal long-term potentiation and recognition memoryBrain Res Bull. (2013)
  25. Effects of Theanine on the Release of Brain Alpha Wave in Adult Males.
  26. Effects of l-theanine on attention and reaction time response.
  27. The acute effects of L-theanine in comparison with alprazolam on anticipatory anxiety in humans.
  28. Pfurtscheller G. Event-related synchronization (ERS): an electrophysiological correlate of cortical areas at restElectroencephalogr Clin Neurophysiol. (1992)
  29. Gomez-Ramirez M, et al. The deployment of intersensory selective attention: a high-density electrical mapping study of the effects of theanineClin Neuropharmacol. (2007)
  30. Visual spatial attention tracking using high-density SSVEP data for independent brain-computer communication.
  31. Kelly SP, et al. Increases in alpha oscillatory power reflect an active retinotopic mechanism for distracter suppression during sustained visuospatial attentionJ Neurophysiol. (2006)
  32. Klimesch W, et al. Induced alpha band power changes in the human EEG and attentionNeurosci Lett. (1998)
  33. Kimura R, Murata T. Effect of theanine on norepinephrine and serotonin levels in rat brainChem Pharm Bull (Tokyo). (1986)
  34. Yokogoshi H, Mochizuki M, Saitoh K. Theanine-induced reduction of brain serotonin concentration in ratsBiosci Biotechnol Biochem. (1998)
  35. Kakuda T, et al. Inhibition by theanine of binding of {3H}AMPA, {3H}kainate, and {3H}MDL 105,519 to glutamate receptorsBiosci Biotechnol Biochem. (2002)
  36. Kakuda T, et al. Theanine, an ingredient of green tea, inhibits {3H}glutamine transport in neurons and astroglia in rat brainJ Neurosci Res. (2008)
  37. Cortese S, et al. Sleep in children with attention-deficit/hyperactivity disorder: meta-analysis of subjective and objective studiesJ Am Acad Child Adolesc Psychiatry. (2009)
  38. Cohen-Zion M, Ancoli-Israel S. Sleep in children with attention-deficit hyperactivity disorder (ADHD): a review of naturalistic and stimulant intervention studiesSleep Med Rev. (2004)
  39. Ritsner MS, et al. L-theanine relieves positive, activation, and anxiety symptoms in patients with schizophrenia and schizoaffective disorder: an 8-week, randomized, double-blind, placebo-controlled, 2-center studyJ Clin Psychiatry. (2011)
  40. Kim TI, et al. l-Theanine, an amino acid in green tea, attenuates beta-amyloid-induced cognitive dysfunction and neurotoxicity: reduction in oxidative damage and inactivation of ERK/p38 kinase and NF-kappaB pathwaysFree Radic Biol Med. (2009)
  41. Schallier A, et al. L-Theanine intake increases threshold for limbic seizures but decreases threshold for generalized seizuresNutr Neurosci. (2013)
  42. Dhir A. Pentylenetetrazol (PTZ) kindling model of epilepsyCurr Protoc Neurosci. (2012)
  43. Gomes A, et al. Proconvulsive effect of tea (Camellia sinensis) in micePhytother Res. (1999)
  44. Takeda A, et al. Unique induction of CA1 LTP components after intake of theanine, an amino acid in tea leaves and its effect on stress responseCell Mol Neurobiol. (2012)
  45. Tian X, et al. Protective effect of l-theanine on chronic restraint stress-induced cognitive impairments in miceBrain Res. (2013)
  46. Joëls M, et al. The coming out of the brain mineralocorticoid receptorTrends Neurosci. (2008)
  47. Sandi C. Glucocorticoids act on glutamatergic pathways to affect memory processesTrends Neurosci. (2011)
  48. Garcia R. Stress, hippocampal plasticity, and spatial learningSynapse. (2001)
  49. Coffee, green tea, black tea and oolong tea consumption and risk of mortality from cardiovascular disease in Japanese men and women.
  50. Peters U, Poole C, Arab L. Does tea affect cardiovascular disease? A meta-analysisAm J Epidemiol. (2001)
  51. Lorenz M, et al. Green and black tea are equally potent stimuli of NO production and vasodilation: new insights into tea ingredients involvedBasic Res Cardiol. (2009)
  52. Siamwala JH, et al. L-theanine promotes nitric oxide production in endothelial cells through eNOS phosphorylationJ Nutr Biochem. (2013)
  53. Owen GN, et al. The combined effects of L-theanine and caffeine on cognitive performance and moodNutr Neurosci. (2008)
  54. Giesbrecht T, et al. The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertnessNutr Neurosci. (2010)
  55. Foxe JJ, et al. Assessing the effects of caffeine and theanine on the maintenance of vigilance during a sustained attention taskNeuropharmacology. (2012)
  56. Haskell CF, et al. The effects of L-theanine, caffeine and their combination on cognition and moodBiol Psychol. (2008)
  57. Einöther SJ, et al. L-theanine and caffeine improve task switching but not intersensory attention or subjective alertnessAppetite. (2010)
  58. Intestinal transport of pure theanine and theanine in green tea extract: Green tea components inhibit theanine absorption and promote theanine excretion.
  59. Varietal Differences in the Total and Enantiomeric Composition of Theanine in Tea.
  60. Desai MJ, et al. Pharmacokinetics of theanine enantiomers in ratsChirality. (2005)
  61. Kitaoka S, et al. Transmural potential changes associated with the in vitro absorption of theanine in the guinea pig intestineBiosci Biotechnol Biochem. (1996)
  62. Kinetics of the sodium-dependent glutamine transporter in human intestinal cell confluent monolayers.
  63. Fiermonte G, et al. Identification of the mitochondrial glutamate transporter. Bacterial expression, reconstitution, functional characterization, and tissue distribution of two human isoformsJ Biol Chem. (2002)
  64. Borzelleca JF, Peters D, Hall W. A 13-week dietary toxicity and toxicokinetic study with l-theanine in ratsFood Chem Toxicol. (2006)
  65. Mutagenicity test of food additives with Salmonella typhimurium TA97 and TA102. X.
  66. Sarris J, et al. L-theanine in the adjunctive treatment of generalized anxiety disorder: A double-blind, randomised, placebo-controlled trialJ Psychiatr Res. (2019)