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3Medicinal

L-theanine

Also sold as Theanine

Calming without sedation; often paired with caffeine.

TrustedSupp Tier System™ · Tier 3Take as a defined course

Evidence strength

55/100Moderate
WEAKLIMITEDMODERATESTRONGVERY STRONG

What the evidence supports: subjective calm and attention, especially with caffeine.

This scores how well-supported the claim above is — not how much benefit you personally would get. A high score on a narrow claim does not extend to everything the product is marketed for.

How long to take it

Ongoing use appears safe; often used situationally.

Who it's actually for

People wanting calm focus, and caffeine users who get jittery.

Safe upper limit

Unverified
No formal limit; 100–400 mg daily in trials
Very well tolerated. Mild blood-pressure lowering at high doses.
No source or citation attached yet.

Interactions to know about

Other supplements:

Run your full list through the interaction check.

Practical notes

  • Roughly 2:1 theanine to caffeine takes the edge off without dulling the lift.