amino acid
L-Theanine
A unique amino acid found primarily in green tea (Camellia sinensis). Promotes relaxation without sedation by increasing alpha brain waves and modulating GABA, serotonin, and dopamine levels.
What it’s good for
L-Theanine for Lack of Focus
Strong2 studies · 1 supporting · 0 against
5 safety notes
Puts you in a calm-but-alert state — steady attention without the jitter of caffeine.
Dose: 100–200 mg
Tested as: L-theanine combined with caffeine
L-Theanine for Anxiety
Solid1 study · 1 supporting · 0 against
5 safety notes
L-theanine reaches the brain and nudges up the chemicals that leave you feeling settled. It takes the edge off without making you drowsy.
Dose: 200–400 mg
L-Theanine for Stress
Solid1 study · 1 supporting · 0 against
4 safety notes
Shifts your brain into a relaxed-but-alert state and takes the edge off cortisol.
Dose: 200–400 mg
L-Theanine for Insomnia
Evidence1 study · 1 supporting · 0 against
5 safety notes
Shifts your brain toward the calm state that comes just before sleep.
Dose: 200–400 mg