The short answer
Small trials suggest possible subjective sleep benefits; it is also an amino acid, not a proven insomnia therapy.
- Evidence and scope
- Conditional or population-specific
This status does not grade the ingredient for every goal, outcome, or person.
- Important limitation
- Benefit depends on the population, formulation, baseline status, and objective; results should not be generalized.
- Before deciding
- Key concern: Kidney/liver disease, pregnancy, clozapine treatment, and large amino-acid stacks require review.
01 / PRACTICAL GUIDE
Dose, absorption, and combinations
These are indication-specific reference or studied ranges—not a personalized prescription. Start with the objective, then check the form, label, medicines, and health conditions.
Reference or studied range—not a personalized prescription. The product label or a clinician may specify a different dose.
Dose source ↗More is not automatically better. A clinician or product label may specify a different amount.
Water-soluble or readily water-dispersible. This does not mean excess is always harmless.
Dissolve in water; timing follows the sleep objective.
Kidney/liver disease, pregnancy, clozapine treatment, and large amino-acid stacks require review.
Dose and use links lead to primary or official source material. Search links are discovery tools, not proof that every returned paper applies.
02 / EVIDENCE
What the research says
We keep supportive, mixed, negative, safety, and contextual findings together. The headline never replaces the underlying papers.
These are audited counts for this JIVANA collection, not search-result totals. Participants are counted once when multiple papers use the same cohort; review papers are not added again to participant totals.
Open the research timelineResearch timeline+
Entries are ordered by publication year. A study period appears only when the source reports it.
Glycine and daytime performance during partial sleep restriction
Fatigue and psychomotor-vigilance reaction time improved selectively, while most computer tasks and melatonin did not. The audit found no participant total in the abstract and the evidence comes from an Ajinomoto research group, so totals are not inferred and broad sleep claims are not supported.
Study design and methods
- Design
- Placebo-comparator human sleep-restriction study
- Population
- Healthy volunteers under short-term partial sleep restriction; the abstract did not report participant count
- Intervention
- Glycine 3 g or placebo before bedtime
- Outcome
- Next-day sleepiness, fatigue, psychomotor vigilance, other computer tasks, melatonin, and circadian measures
Funding or conflict note: The corresponding author was affiliated with Ajinomoto's research laboratories.
Unscreened discovery appendix—not evidence1 candidate publicationsSearch run: Aug 21, 2026
Complete for the displayed PubMed query at the search timestamp—not for all databases or every possible synonym. Candidates can be irrelevant, duplicate the same study, or report negative findings. They are never summed as evidence or participants until screened.
03 / SOURCES
Start with the source material
The live search is for discovery only. Search-result counts change and are not included in the audited totals above.
Recent PubMed discovery recordsDirect links to the first 12 records returned by the reproducible search. These are discovery candidates—not reviewed summaries or a count of supportive findings.
04 / EXPERT CONTEXT
Expert context—not evidence
Expert positions are dated context—not scientific evidence. They never raise the evidence status or become consensus by repetition.
No direct, source-verified endorsement is currently recorded. Research authorship or discussion alone is not treated as endorsement.