L Theanine

About L Theanine

L theanine is a non protein amino acid, chemically gamma glutamylethylamide, found almost exclusively in the tea plant Camellia sinensis and in a few mushrooms such as the bay bolete. It was identified in tea leaves in 1949 by Japanese researchers and is responsible for much of the savory umami taste of green tea. Theanine is synthesized in tea roots from glutamate and ethylamine and transported to the leaves; shading tea bushes before harvest, as is done for gyokuro and matcha, limits its conversion into catechins and keeps levels high. Structurally similar to glutamate, it crosses the blood brain barrier and has been reported to influence GABA, serotonin and dopamine signaling, and studies using electroencephalography have associated it with increased alpha wave activity, a pattern linked to relaxed wakefulness. Small human trials have examined theanine alone and combined with caffeine for attention, reaction time, stress and sleep quality, generally finding modest effects. L theanine is generally recognized as safe as a food ingredient in the United States.