Natural Factors Stress Relax Mental Calmness Chewable 120’s100mg 120 Chewable Tablets Mental Calmness This is the feel good amino acid found in green tea. Studies show that L Theanine produces tranquilizing effects in the brain without drowsiness. It calms by helping to increase alpha brain waves, the electrical brain activity commonly present when you are very relaxed. By diminishing the feeling of stress, worry and anxiety, L Theanine may actually help with focus, learning and concentration.