L-Theanine:

L-Theanine: L-Theanine is a non-essential amino acid. L-theanine may affect the levels of certain chemicals in the brain. These include serotonin and dopamine, which influence mood, sleep, and emotion, and cortisol, which helps the body deal with stress.  L-theanine may offer a range of benefits to include increasing cognitive function and mood, reducing stress level and blood pressure, reduced anxiety and depression, better sleep, and mental focus.