L-Theanine
Also known as: L-Theanine, N-ethyl-L-glutamine
Effective Dosage
100-400 mg daily
✓ What the Science Says
L-Theanine is an amino acid primarily found in tea leaves, known for its calming effects without sedation. It has been shown to reduce stress and anxiety, improve focus, and enhance cognitive performance, particularly when combined with caffeine.
✗ What It Doesn't Do
L-Theanine is not a sedative and does not induce sleep; it may help with relaxation but should not be marketed as a sleep aid. Additionally, it does not cure anxiety disorders or replace prescribed medications.
Evidence-Based Benefits
L-Theanine is an amino acid primarily found in tea leaves, known for its calming effects without sedation. It has been shown to reduce stress and anxiety, improve focus, and enhance cognitive performance, particularly when combined with caffeine.
Strong EvidenceEffective at: 100-400 mg daily
Source: auto-research
Absorption & Bioavailability
Good - L-Theanine is well absorbed in the gastrointestinal tract.
Red Flags to Watch For
- 🚩 Claims of miraculous anxiety cures
- 🚩 Products that suggest it can replace medication without evidence
Products Containing L-Theanine
See how L-Theanine is used in these analyzed products:
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-02-05