Origin & tradition
Not traditional as a supplement: glycine is the simplest amino acid, abundant in collagen and connective tissue.
Western tradition · Amino Acid
Glycine
A conditionally essential amino acid that becomes deficient with age and suppresses mTORC1 — extended median lifespan 28% in NIH mice studies.
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Why longevity buyers care
Key active: Glycine (conditionally essential amino acid).
Glycine is rate-limiting for glutathione synthesis alongside cysteine, and is required for collagen and creatine biosynthesis. It also suppresses mTORC1 via its sensor GCN2. Glycine supplementation extended median lifespan in mice by 28–31% (NIH ITP). The GlyNAC combination (2021 Baylor RCT) corrected multiple aging hallmarks in older adults.
Effect summary
Studied health outcomes
Editorial summary — This table is curated by hand from published research consensus, not automatically calculated from our trial database. Grades reflect our interpretation of the literature. Treat as a starting point, not a definitive verdict. See the Evidence panel below for the underlying trial and paper counts sourced directly from ClinicalTrials.gov and PubMed.
| Health outcome | Effect | Magnitude | Grade |
|---|---|---|---|
| Sleep quality and onset | Increases | Moderate | B |
| Glutathione levels (with NAC) | Increases | Moderate | B |
| Collagen synthesis markers | Increases | Moderate | B |
| Fasting blood glucose | Decreases | Minor | C |
| Core body temperature at night | Decreases | Minor | B |
Grade: A = robust RCTs · B = several RCTs / meta-analysis · C = limited or mixed RCTs · D = observational or early data
Dosage guidance
How Glycine is typically used
- Typical dose
- 3–5 g/day powder
- Form
- powder (sweet taste, mixes easily)
- Timing
- 30–60 minutes before bed for sleep; any time for other effects
Glycine is an inhibitory neurotransmitter that lowers core body temperature, aiding sleep onset. Also the rate-limiting precursor (with NAC) for glutathione. Widely available and inexpensive. Very safe — dietary intake from collagen-rich foods is 2–5g/day.
Informational only — not a prescription or personalised medical advice. Consult a qualified clinician before starting any supplement or medication.
Evidence summary
What the research actually says
74Evidence confidence
Extensive human-trial evidence1,722 randomized controlled trials · 399 meta-analyses / systematic reviews
Strong NIH preclinical lifespan data; GlyNAC human RCT; direct aging trials limited
Glycine is rate-limiting for glutathione synthesis alongside cysteine, and is required for collagen and creatine biosynthesis. It also suppresses mTORC1 via its sensor GCN2. Glycine supplementation extended median lifespan in mice by 28–31% (NIH ITP). The GlyNAC combination (2021 Baylor RCT) corrected multiple aging hallmarks in older adults.
4registered clinical trials reference this intervention
0selected peer-reviewed papers (longevity / aging angle)
Key active: Glycine (conditionally essential amino acid).
According to PubMed and ClinicalTrials.gov: trial counts from ClinicalTrials.gov, peer-reviewed literature from PubMed. Counts auto-refresh weekly; last checked 2026-06-12. They include trials across many endpoints, not only longevity.
Informational only — not medical advice, a treatment claim, or a substitute for a qualified clinician. Evidence strength varies; we show mixed and null results on purpose.
Evidence collections
Glycine appears in
Compare the evidence
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Compare the evidence
How Glycine stacks up
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