About
What it is and where it shows up.
L-theanine is a non-protein amino acid naturally found in the leaves of Camellia sinensis (tea plant), constituting approximately 50% of total free amino acids in green tea. It is used as a functional food ingredient and dietary supplement for its reported relaxation, stress-modulating, and cognitive-support properties.
Safety summary
The regulatory and scientific consensus.
L-theanine holds FDA GRAS status (GRN 209, 338, 501) and clinical trials at doses up to 400 mg/day in healthy adults have reported no clinically relevant adverse effects. No formal ADI has been established by any major regulatory body. Precautionary exclusions in the ongoing EU Novel Food application cover children under 18 and pregnant or lactating women due to insufficient safety data for these groups.
Regulatory landscape
What food-safety regulators have decided.
| Jurisdiction | Status | Note |
|---|---|---|
| FDA (Food and Drug Administration) (United States) | Approved | GRAS status established via multiple notices: GRN 209, GRN 338, and GRN 501 (chemically synthesized L-theanine). No maximum daily intake formally set by FDA. Also recognized as a dietary supplement ingredient under 21 CFR.source |
| EFSA (European Food Safety Authority) (European Union) | Under_review | L-theanine is under active review as a Novel Food under Regulation (EU) 2015/2283 (application 2024-15277). Use sought in food supplements only. Children under 18, pregnant women, and lactating women are explicitly excluded from the proposed target population. No E number assigned.source |
| FSSAI (Food Safety and Standards Authority of India) (India) | Under_review | L-theanine is not listed as a standard food additive in FSSAI Food Products Standards and Food Additives Regulations 2011. Ingredient applications for non-specified food ingredients may be submitted under FSS (Approval for Non-Specified Food and Food Ingredients) Regulations 2017. No confirmed specific standalone approval found in available FSSAI records.source |
Who should approach with care
Whose guidance would steer them away.
Pregnancy — The EU Novel Food application explicitly excludes pregnant women from the proposed target population due to insufficient safety data during pregnancy.
Lactation — The EU Novel Food application explicitly excludes lactating women from the proposed target population due to insufficient safety data during breastfeeding.
Children — The EU Novel Food application excludes children under 18 from the proposed target population, and dedicated pediatric safety studies are lacking.
Research citations
The sources behind this verdict.
- 1FDA. GRAS Notice No. 501 – L-theanine (chemically synthesized). hfpappexternal.fda.gov
- 2PubMed. Safety and Efficacy of AlphaWave® L-Theanine Supplementation for 28 Days in Healthy Adults with Moderate Stress: A Randomized, Double-Blind, Placebo-Controlled Trial, 2024. pmc.ncbi.nlm.nih.gov
- 3other. EU Novel Food Application Summary – L-Theanine (Application 2024-15277), 2024. food.ec.europa.eu
- 4PubMed. L-theanine: an astounding sui generis amino acid in poultry nutrition, 2020. pmc.ncbi.nlm.nih.gov
- 5EFSA. Scientific Opinion on the substantiation of health claims related to L-theanine from Camellia sinensis (L.) Kuntze (tea) and improvement of cognitive function, alleviation of psychological stress, maintenance of normal sleep and reduction of menstrual discomfort pursuant to Article 13(1) of Regulation (EC) No 1924/2006, 2011. efsa.europa.eu
Independently researched5 citations