Glycine
Sleep · Amino acid / NMDA co-agonist
Tier B-
What this is
Ajinomoto-era Japanese research tradition demonstrated modest but consistent subjective sleep quality improvements. Cheap, safe, no tolerance. Sweet taste makes it easy to take. Component of GlyNAC protocol for glutathione (separate from sleep use).
Mechanism
Simple amino acid; NMDA receptor co-agonist; inhibitory at spinal cord via glycine receptors; reduces core body temperature which aids sleep onset; modest sleep quality improvement in Japanese trials
Dose & route
3 g PO 30-60 min before bed
Citations
- https://pubmed.ncbi.nlm.nih.gov/17341027/
- https://pubmed.ncbi.nlm.nih.gov/22293292/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC7589578/
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This is an independent synthesis of published research by a non-clinician. Scores are opinions supported by citations, not prescriptions. See the full disclaimer and methodology for how this score was produced and what it does and doesn't mean.