Gamma-Aminobutyric acid (GABA) is a major neurotransmitter in our central nervous system and its stimulation might bring about calming effects, as well as restful sleep. L-Theanine is a component of green tea that is thought to traverse the blood-brain barrier, potentially leading to elevated alpha waves which can cause relaxation thanks to GABA-receptor stimulation. Additionally, L-Theanine has been demonstrated to support cortisol output and reduce hunger.