L-Theanine is a non-protein amino acid that is naturally found in green tea. L-Theanine is not found in any food, other than a rare species of mushrooms. Theanine promotes relaxation, rejuvenation, and focus. Multiple studies have shown that theanine supports focus and concentration without the intense jitters you would commonly have after having an energy drink. Theanine exerts its efforts on several fronts, by supporting levels of inhibitory neurotransmitters in the brain and promoting a state of relaxation in the brain. For example, L-theanine supports levels of GABA in the brain to promote a relaxed sensation, also the effects of theanine is believed to have a big impact on alpha brain wave activity, which is believed to help with an alert, and relaxed state of mind. As theanine may sound great as a bedtime supplement, it still has many great effects when paired with caffeine.