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Proven · 7.9/10

L-Theanine

Evidence B · good evidence ▼ 7.0% momentum 🥇 First scout open
7.9/ 10

L-Theanine is the calming amino acid from tea. It works best as an alert-calm stack with caffeine, where trials such as Owen 2008, Giesbrecht 2010, Kelly 2008, and Haskell 2008 support attention and reaction-time benefits beyond caffeine alone. Standalone benefits are more modest: stress and sleep look real but not guideline-grade, with newer reviews from Bulman 2025, Cotter 2026, and Moshfeghinia 2024 strengthening but not closing the evidence gaps. Read the full breakdown →

The prediction game

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The Crowd’s Call

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Your 12-month call on L-Theanine

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For education only, not medical advice. Supplements, peptides, and protocols can interact with medications and conditions. Talk to a qualified clinician before starting anything here.