Mental Clarity with L-Theanine

L-theanine crosses the blood-brain barrier and affects brain activity by promoting a state of deep relaxation and mental alertness, via effects on alpha brain wave activity (such as often achieved with meditation).[1]

L-theanine is a naturally occurring amino acid found in tea that may enhance cognitive function, reduce acute stress and anxiety, and improve sleep quality.[2]

During demanding cognitive tasks, Theanine may help improve executive functioning, attention and focus.[2,3,4] Older adults showed improvements in cognitive function and working memory after a single dose of L-theanine.[5]

[1] Mason R. 200 mg of zen: L-theanine boosts alpha waves, promotes alert relaxation. Altern Complement Ther. 2001 Apr;91-95. DOI:10.1089/10762800151125092

[2] Hidese S, et al. Effects of L-theanine administration on stress-related symptoms and cognitive functions in healthy adults: a randomized controlled trial. Nutrients. 2019 Oct;11(10):2362. DOI: 10.3390/nu11102362

[3] Gomez-Ramirez M, et al. The effects of L-theanine on alpha-band oscillatory brain activity during a visuo-spatial attention task. Brain Topogr. 2009 Jun;22(1):44-51. DOI: 10.1007/s10548-008-0068-z

[4] Gomez-Ramirez M, et al. The deployment of intersensory selective attention: a high-density electrical mapping study of the effects of theanine. Clin Neuropharmacol. 2007;30(1):25-38. DOI: 10.1097/01.WNF.0000240940.13876.17

[5] Baba Y, Inagaki S, Nakagawa S, Kaneko T, Kobayashi M, Takihara T. Effects of L-theanine on cognitive function in middle-aged and older subjects: a randomized placebo-controlled study. J Med Food. 2021 Apr;24(4):333-341. DOI: 10.1089/jmf.2020.4803