Substrate ·evidence-based
interventions / Glycine / sleep

Does Glycine help sleep? (Grade C evidence)

Explore current source-reported research for this exact question. These records are separate from the synthesis below; they do not update its grade or establish a recommendation.

For sleep, Glycine sits at Grade C — a hint of benefit in the recorded evidence, especially in adults, low certainty, at doses 3 g before bed.

Exact question reviewed

Population
adults
Intervention
Glycine · 3 g before bed
Comparator
not reported
Outcome
sleep
Time horizon
not reported

Bottom line. For sleep, Glycine sits at Grade C — a hint of benefit in the recorded evidence, especially in adults, low certainty, at doses 3 g before bed. [1 other]

Direction
benefit
Magnitude
small trials suggest improved subjective sleep quality and reduced next-day fatigue
Grade
C
Certainty
low
Clinical meaning
small but potentially useful
Who it applies to
adults
Dose / form studied
3 g before bed
Safety
not assessed
The one limitation
Claim-specific limitation details are not available in this public record.

Reviewed not reported · Evidence last changed · Open evidence record (version 0)

Grade
C
what does the grade mean?
Certainty
low
what does certainty mean?

Grade C / low: hints of benefit in small trials; a well-run RCT could easily push this to B or to null.

Who it works for

Best-studied in adults. Recorded studied dose: 3 g before bed.

Evidence

StudyDesignRoleCite
New therapeutic strategy for amino acid medicine: glycine improves the quality of sleeppeer-reviewednot classifiedPMID:22293292

Why this grade

Reasoning trace

The current record stores Grade C at low certainty and links 1 publishable source. A claim-specific domain-by-domain grading rationale is not available in this public record, so no reason for upgrading or downgrading is inferred here.

Audit and version

Claim ID
ec_gly_sleep
Claim version
not reported
Governance
legacy, not verified
Clinician review
Not yet reviewed by a licensed clinician
Last evidence search
not reported
Last editorial review
not verified

Public receipt · Machine-readable claim · Methodology

Dose & form

Studied intake: 3 g before bed.

How it stacks up for sleep

Grade history

Re-review cadence: every 6 months (Grade C+) · methodology v1.

Frequently asked

How long does Glycine take to work for sleep?

This record does not report a studied onset time for Glycine and sleep. Do not assume a typical timeframe.

What dose was used in studies of Glycine for sleep?

The recorded studied dose for Glycine and sleep is 3 g before bed. This is a source detail, not a dose recommendation.

Does Glycine work for sleep if I'm not deficient?

The recorded studied population is adults. This field alone does not show whether deficiency or baseline status changes the effect.

Glycine or the next-best alternative for sleep?

See the compare block above for the head-to-head with the most-cited alternative. Grade + certainty differences matter more than any single trial.

Related

What this is — and is not

Evidence description
small trials suggest improved subjective sleep quality and reduced next-day fatigue
Substrate's interpretation
The current reviewed record assigns Grade C at low certainty. A domain-by-domain rationale is shown only when recorded.
Discuss with a clinician
If you're on medication or have a condition that changes the calculus, bring the interaction & population blocks above to your pharmacist or prescriber before deciding.
Individualized medical advice
Not provided here or on any Substrate surface (API, agent tool, embed) — see YMYL policy.

Cite this page

Citation is encouraged. The proposed reuse license is CC-BY-4.0; status: pending-governance-ratification.

Plain-text citation
Substrate. Does Glycine help sleep? (Grade C). https://evidencebased.info/interventions/glycine/sleep. Updated 2026-07-16.
BibTeX
@misc{substrate_ventionsglycinesleep,
  author = {Substrate editorial},
  title  = {Does Glycine help sleep?},
  year   = {2026},
  url    = {https://evidencebased.info/interventions/glycine/sleep},
  note   = {Grade C, evidencebased.info}
}

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Current source-reported research

Membership uses admitted intervention and measured-outcome associations for this exact question. Different populations, preparations, comparators and timepoints remain separate. No pooling or update to the synthesis is asserted.