Amino acid
L-Theanine
In short
L-theanine is an amino acid found naturally in tea leaves. It’s sold alone or combined with caffeine or magnesium. SuppScout’s evidence review for L-theanine is in progress.
Research in progress. This ingredient page doesn’t yet meet SuppScout’s bar for a complete reference (sourced evidence summary, considerations and sufficient detail), so search engines are asked not to index it. The information shown is sourced where cited.
Quick facts
- Found in
- Tea (Camellia sinensis)
Common l-theanine supplement forms
- L-theanine (free form)
- Branded fermentation-derived L-theanine
Detailed form pages for L-Theanine are being researched.
Food sources
- Green and black tea
Potential considerations
- Evidence summary not yet published — check back as this page is researched.
Products containing l-theanine
No products listed yet
SuppScout hasn’t added l-theanine products yet.
This page is educational and is not medical advice. Talk to a healthcare professional before starting a supplement, especially if you have a medical condition, take medications, or are pregnant or breastfeeding. Medical disclaimer.