Amino & PerformanceNo.053

L-Theanine

Calm focus, takes the edge off caffeine.

Typical / RDA100–200 mg

Upper limitWell tolerated

EvidenceModerate

How to take it

Timing With caffeine / AMFood OptionalForm Pure L-theanine

What to know

An amino acid from tea that promotes relaxed alertness without drowsiness. Commonly paired with caffeine to smooth out jitters. Low risk.

Interactions & cautions

May mildly lower blood pressure — minor for most.

Do you actually need it?

A reasonable, low-risk trial for focus with coffee.

Questions people ask about l-theanine

Can You Take Too Much L Theanine? Side Effects and Daily LimitsL-Theanine is generally well-tolerated, with typical doses of 100-200 mg. While there's no defined upper limit, very high doses may mildly affect blood pressure.
Can you take L-theanine with melatonin for better sleep?L-theanine and melatonin are safe to combine for sleep, working through different pathways to promote relaxation and regulate your sleep cycle. Learn how to use them effectively.
Does L-Theanine Really Help With Focus and Concentration?L-Theanine can promote calm focus without drowsiness. Doses of 100–200 mg are common for this effect, often paired with caffeine.
Best Supplements for Sleep: Melatonin, L-Theanine, and ValerianMelatonin, L-Theanine, and Valerian Root may offer some help for sleep, but results vary. Melatonin is best for clock shifts, L-Theanine for calm, and Valerian for general relaxation.

See how this fits your full stack →

Reference values: NIH Office of Dietary Supplements, adult general population. Educational information only — not medical advice. Confirm with a healthcare professional.