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Ingredient

Glycine

Promising

A simple amino acid studied for subjective sleep quality at modest pre-bed doses.

How it works

Acts as an inhibitory neurotransmitter and may modestly lower core body temperature near sleep onset.

Evidence

Small Japanese trials report improved subjective sleep quality with 3 g pre-sleep glycine.

Studies

Yamadera et al., Sleep Biol Rhythms, 2007
Improved subjective sleep quality and reduced fatigue with 3 g pre-bed glycine.
PubMed 22293292 ↗

One ingredient, one study, one product worth your money.

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