The libraryCalm
L-Theanine
Anxiety under acute stress is what it's actually moved in healthy adults.
Also called Theanine, N-ethyl-L-glutamine, γ-glutamylethylamide, Suntheanine
Who it's forAny man whose coffee leaves him wired, tense and useless for an hour.
The item
Three squares: proven in human trials. Two: a strong signal. One: early human data. Striped: the trials disagree.
Start today
- Drop a theanine capsule in with tomorrow morning's first coffee.
Why it works
It is close enough in shape to glutamate to work with the systems glutamate uses, and it crosses into the brain easily. It binds weakly at glutamate receptors and gets in the way of glutamate transport. That gently damps excitatory signaling without sedation, and it raises GABA too. That is why it takes the edge off caffeine without making anyone sleepy.
Where it fits
L-Theanine is a move in 9 protocols. Each one opens the plan it sits in.
What people say
Here is what doctors, influencers and men online say about L-Theanine, word for word.
Experts
Clinicians, authorities
“L-theanine has been shown to promote relaxation and reduce stress without causing drowsiness.”
“L-theanine is a chemical found in both green and black tea. It helps you relax by lowering stress and anxiety”
“It appears that L-theanine may support relaxation and stress reduction, but larger studies are needed to confirm these findings.”
Gurus
Podcasts, channels, influencers
“Don’t take theanine if you have overly intense dreams, sleep-walk, or have night terrors.”
“My goal was to eliminate the physical & mental “twitchiness” of caffeine, which subjectively it seems to do.”
“I will say also that I am a big fan of L-Theanine for a number of reasons. It’s really helpful for, in some respects, taking the edge off of coffee consumption.”
Regular people
Forums, reviews, comments
“has an average rating of 4.4 out of 5 from 177 reviews on WebMD. About 91% of reviewers reported a positive effect.”
“The only disagreement I would have is the high rating of l-theanine, didn’t do much for me”
“L-Theanine has only been weakly shown to relax people, and has had no scientific consensus that it improves attention.”
The studies
Every study behind this page.
- Cognitive and affective effects of L-Theanine: a systematic review and meta-analysis of 31 randomized trialsPubMed, PMID 42410082
- The effects of L-theanine consumption on sleep outcomes: A systematic review and meta-analysisPubMed, PMID 40056718
- Effects of Tea (Camellia sinensis) or its Bioactive Compounds l-Theanine or l-Theanine plus Caffeine on Cognition, Sleep, and Mood in Healthy Participants: A Systematic Review and Meta-Analysis of Randomized Controlled TrialsPubMed, PMID 40314930
- The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systematic ReviewPubMed, PMID 31758301
- Theanine and cancer: A systematic review of the literaturePubMed, PMID 33891786
- Registered trial NCT07682532Trial registry
- Registered trial NCT07220447Trial registry
- Registered trial NCT07189442Trial registry
- Registered trial NCT05854017Trial registry
Words on this page
- PMID
- A study's ID number in PubMed, the public index of medical research.
Stack theanine with your coffee. It takes the jitter out without making you dull.
Emergency: call 911.
I am not a doctor. This is not medical advice. This is self-education. Talk to a physician who has your history before you change anything.