Evidence brief · Supplement

L-Theanine for Attention (with caffeine)

Evidence grade B — Smoother focus, less jitter

Overall grade
Grade B
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 B — 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.

  • Attention (with caffeine)Evidence grade B

    Smoother focus, less jitter

    Moderatehigh

The evidence in words

The verdict

For attention (with caffeine), L-Theanine earns evidence grade B (moderate effect, high consistency) — there is real evidence here. Smoother focus, less jitter

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

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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.