Amino Acid
L-Theanine
Also known as: Theanine
A
Evidence
Calming amino acid from tea that promotes relaxation without sedation. Synergistic with caffeine for focused calm.
Primary uses
- Relaxation
- Focus
- Sleep support
- Anxiety relief
How it works
- Increases alpha brain waves
- Modulates GABA, dopamine, serotonin
- Crosses blood-brain barrier
Dosage
- Typical range
- 100-400 mg daily
- Timing
- Any time; with caffeine for focus
- With food
- Optional
- Duration
- Safe long-term
- Special populations
- Anxious, need calm focus
Forms
- Capsules
- Powder
- Tea
Safety
Common side effects
- Very well tolerated
Contraindications
- None
Known interactions
Evidence notes
Well-studied for calm focus
Grade A: Multiple well-designed human trials support the main claims.
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