HealthStylz

Supplements

L-theanine

Stress, anxiety and sleep support.

Few studies so far

You need a day
Not set
Most pills have
200 mg
Safe max a day
Not set
Careful studies
17
Hands whisk matcha in a bowl on a warm wooden tablePhoto: Ivan S
See what the molecule looks like

Drag to turn · 12 heavy atoms · PubChem CID 439378

L-Theanine. Drag to turn it.

What the research says

The short version

A 2020 review of 9 trials found 200 to 400 mg a day may ease stress and anxiety in stressed people. A 2025 meta-analysis of 18 trials found small gains in sleep onset time and sleep quality.

The right dose and duration are not established, and no government safety sheet was found.

About "most pills": 2020 systematic review of 9 trials: 200 to 400 mg a day may reduce stress and anxiety in people under stress.

Sources: pubmed.ncbi.nlm.nih.gov, pubmed.ncbi.nlm.nih.gov

Who is reading about it

About 372 people a day read about L-theanine

That is +8% compared with the month before. The busiest day lately was Sep 10, 2026.

Wikipedia article "Theanine", daily readers, last 90 days.

Our stories

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