Evidence brief · Supplement
L-Theanine for Sleep quality
Evidence grade C — Relaxation, not sedation
- Overall grade
- Grade C
- Last revised
- 1
- graded outcome
- 0
- references listed
Assembled by the app from other entries in this library. It adds no evidence of its own — follow the links to the entries it draws on.
1 at grade C — 1 graded row
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Sleep qualityEvidence grade C
Relaxation, not sedation
Smallmixed
What is uncertain
Read off the same rows as above. Nothing here is added that the entry does not itself record.
- Thin evidence: Sleep quality (grade C).
The evidence in words
The verdict
For sleep quality, L-Theanine earns evidence grade C (small effect, mixed consistency) — the evidence is limited or mixed. Relaxation, not sedation
How it might work
Theanine increases alpha brain-wave activity (a relaxed, attentive state) and modulates glutamate and GABA signaling. Combined with caffeine it appears to preserve the alertness while blunting the anxiety, jitter, and blood-pressure bump.
How to use it
100–200 mg, often paired ~1:1 to 2:1 with caffeine (e.g., 200 mg theanine with 100 mg caffeine). Can be used standalone for stress or before sleep.
Safety & cautions
Very safe and non-sedating; no meaningful toxicity or dependence.
Bottom line
The evidence-backed way to civilize caffeine: 200 mg theanine with your 100 mg caffeine for cleaner focus. Also a gentle standalone de-stressor.
How it is used
As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.
- Focus stack
- 200 mg with 100 mg caffeine.
- Calm
- 100–200 mg standalone.
Goes with
- L-TheanineRead the full L-Theanine monographEvidence grade B
Related reading
Entries that share this one's tags or conditions.
- L-Theanine for Acute stress / anxietyEvidence grade B — Non-sedating calmEvidence grade B
- L-Theanine for Attention (with caffeine)Evidence grade B — Smoother focus, less jitterEvidence grade B
- L-Theanine: dosage and how to take it200 mg with 100 mg caffeine.Evidence grade B
- L-Theanine: side effects, safety & interactionsVery safe and non-sedating; no meaningful toxicity or dependence.Evidence grade B
Sources
This entry lists no references of its own — it is assembled from the entries it links to, whose sources are on their pages.
Last revised . A grade is this entry's reading of the evidence, not medical advice.