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Best for Stress & Mood

Best Theanine for Stress & Mood

Top 30 products ranked · Reviewed May 2026 · 100–250 mg clinical dose

Why Theanine for Stress & Mood

Theanine plays a important role in stress & mood. L-Theanine is an amino acid found in tea leaves. It promotes relaxation without drowsiness and may support sleep quality when combined with other sleep aids.

What dose to look for

Clinical studies typically use 100250 mg of theanine. Common supplemental range; 200 mg is the most studied single dose for relaxation and focus. Products below this range may not deliver meaningful results.

What the research says

Theanine has moderate clinical evidence for stress & mood benefits. Several clinical trials on relaxation and focus, most using 200mg; consistent but modest effects Learn more

Clinical research on L-Theanine

HIGH — 18+ RCTs, consistent subjective benefits · 200–400 mg/day (do NOT exceed 655 mg)

  • 2025 meta-analysis of 18 RCTs (897 participants) found improved sleep quality (SMD=0.43, p=0.03) and daytime dysfunction (SMD=0.33, p<0.001). Objective measures (actigraphy, PSG) did not improve.
  • 2024 RCT (200 mg/day, 4 weeks) reduced stress (SDS), trait anxiety (STAI), sleep disturbance (PSQI), and improved verbal fluency.
  • AlphaWave single-dose RCT (200 mg) increased alpha brain waves, reduced anxiety, and lowered salivary cortisol.
  • Mechanism: increases alpha waves and modulates GABA, serotonin, and dopamine — producing relaxation without sedation. Acute effects same day; cumulative benefits at 2–4 weeks.
See full Stress & Mood research

Top 30 Theanine products