Theanine is an amino acid found mostly in Green Tea. It is famously known for its effect as a mood enhancer and it promotes relaxation. In this respect it can counter the stimulation that caffeine provides to the nervous system. It is also found in isolated form on the market. Its calming effect is the result of stimulating the production of alpha brain waves, resulting in a state of deep relaxation and mental alertness. Second, Theanine is involved in the formation of gamma amino butyric acid (GABA)an inhibitory neurotransmitter which influences the levels of two other neurotransmitters, dopamine and serotonin both well-known promoters of relaxation.