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Evidence-Based Supplement Research

Evidence-Based Supplement Research

L-Theanine and Reduced Anxiety

Doses used in studies

mg/day: 200 (median 200, IQR 200–200) — 1 study
mg/kg/day: 3 (median 3, IQR 3–3) — 1 study

2 of 2 papersPopulation:

Performance-enhancing effects of caffeine and L-Theanine among Iranian elite wrestlers: a focus on cognitive and specific physical performance.
- 2025-09-22
- RCT
- Journal of the International Society of Sports Nutrition 22(1)
- - Rouzbeh Razazan
  - Mohammad Hemmatinafar
  - Babak Imanian
  - Nima Jahaniboushehri
  - Rasoul Rezaei
  - Gholamhossein Nazemzadegan
- PubMed: 40977612
- DOI: 10.1080/15502783.2025.2564238
9 Insights on
- Reduced Anxiety
- High evidence
- Athletes
CAF+THE reduced anxiety to below placebo levels (8% incidence vs 33%).
Effect
Neutral
Effect size
Small
Significant
No
Dose
3 mg/kg
Impact of L-theanine and L-tyrosine on markers of stress and cognitive performance in response to a virtual reality based active shooter training drill.
- 2024-07-08
- RCT · n = 28
- Stress (Amsterdam, Netherlands) 27(1)
- - Matthew J McAllister
  - M Hunter Martaindale
  - Courtney C Dillard
  - Rory McCullough
- PubMed: 38975711
- DOI: 10.1080/10253890.2024.2375588
5 Insights on
- Reduced Anxiety
- High evidence
- Adults
Ingestion of L-theanine and L-tyrosine did not impact markers of stress.
Effect
Neutral
Effect size
Small
Significant
No
Dose
200 mg