With a chemical structure very similar to glutamine, L-theanine is an amino acid with a reputation for being a relaxing agent without causing sedation.
Found mainly in green tea, multiple studies have shown L-theanine notably increases relaxation as assessed by neural measurements such as alpha waves. Animal neurochemistry studies suggest that L-theanine increases brain serotonin, dopamine and GABA levels and has affinities for several glutamate receptor subtypes. These properties may also go to explain how L-theanine exerts its neuroprotective effects. Behavioural studies in animals suggest improvement in learning and memory.
Overall, L-theanine displays a neuropharmacology suggestive of a possible neuroprotective and cognitive enhancing agent. This certainly makes it a worthwhile consideration as a supplement for learning and memory.
In this infographic we examine L-theanine as it relates to cognition, learning and focus. We also explore the areas of the brain and the specific neurotransmitters that L-theanine has been shown to influence.
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