What is theanine?

Theanine is also known as L-γ-glutamylethylamide and N5-ethyl-L-glutamine. It is unique amino acid present almost exclusively in the tea plant (Camellia sinensis), where typically occurs in amounts estimated from 1 to 2% by dry weight.

It is thought that theanine makes a significant contribution of the flavor of the tea beverage which is dominated by the bitter taste of the polyphenols and caffeine. L-Theanine is absorbed through the intestinal tract and is hydrolyzed to glutamic acid and ethylamine in the kidney.

L-Theanine may have mood-modulating activity and is able to cross the blood brain-barrier and improve human brain’s reaction to stress. This amino acid actually acts antagonistically against the stimulatory effects of caffeine on the nervous system.

It may also play a role in the formation of GABA, a neurotransmitter that is important for sleep, and memory. L-Theanine also affects the balance of dopamine and serotonin in the brain to create a relaxation effect.
What is theanine?