L-theanine is a unique amino acid found only in green tea and certain mushrooms. It counteracts the effects of caffeine and not surprisingly, green tea is not as stimulating as coffee. L-theanine crosses into the brain and affects neurotransmitters in such a way as to induce calmness, support positive mood, and improve mental focus. It counters the negative effects of stress-induced adrenaline secretion and can lower blood pressure in hypertensive individuals. It does not cause sedation during the day, but does promote natural sleep at night.

Suggested Dosage: 200 mg one to two times daily.

Side effects: Almost unheard of. L-theanine is widely consumed in green tea by millions of people every day. Because l-theanine is metabolized by the same pathways as other amino acids in the body, there appears to be little risk of tolerance and dependence.