Strong evidenceamino_acid

L-Theanine for Stress

L-theanine increases alpha brain wave production (8-14 Hz), creating a relaxed-but-alert mental state. It reduces cortisol and enhances GABA activity, counteracting the physiological effects of acute and chronic stress.

How strong is the research?

Strong evidence

Based on a randomised controlled trial (RCT) — the gold standard for establishing cause and effect.

Research source

SourceHidese S et al. · Nutrients 2019

How much to take

200–400 mg

Works within 30-40 minutes for acute stress. Can be combined with ashwagandha for comprehensive stress support.

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