L-Theanine

theaninetheanin

Nootropic

L-Theanine is an amino acid found in green tea that can help you relax and focus. It's often used to reduce stress and anxiety, and improve sleep quality.

Low Concern

Source: FDA GRAS list

L-Theanine is generally considered safe when consumed in moderation, but high doses may cause drowsiness or interact with certain medications.

What is L-Theanine? Sleep & Anxiety? [Benefits, Side Effects & Dosage]

What is L-Theanine? Sleep & Anxiety? [Benefits, Side Effects & Dosage]

Michigan Foot Doctors

r/NooTopics

Nootropics Map

Promising, but Not Completely Conclusive-The Effect of l-Theanine on Cognitive Performance Based on the Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Clinical Trials.

Mátyus RO, Szikora Z, Bodó D

2025

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Last updated: May 16, 2026

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