L-theanine is a unique, non-proteinogenic amino acid found almost exclusively in the tea plant (Camellia sinensis) and has been safely used in Japan for decades. The patented Suntheanine® has been the subject of at least 50 studies over the past 20 years.
A Japanese study showed 200 mg of L-theanine increased alpha waves and relaxation, promoting a calm yet focused state, starting about 40 minutes after intake.
