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GlyNAC (Glycine + NAC)

Also known as: Glycine and N-acetylcysteine, Glycine + NAC

Preliminary evidenceAmino acid combinationPartially reviewedHigh cautionHealthy AgingGeneral Wellness

GlyNAC refers to taking glycine together with N-acetylcysteine (NAC). The rationale, discussed in mechanism and small-trial literature, is that the body makes glutathione from cysteine (supplied by NAC) and glycine, so providing both may support glutathione synthesis. Human trials are small and early — several involved older adults or specific patient groups — and the combination is not established as necessary or beneficial for the general population. Because it includes NAC, the same bleeding, asthma, and regulatory cautions apply. This entry is informational; it is not a recommendation to take the combination.

Not medical advice. SuppSafety and StackWise are informational only. Talk to a qualified healthcare professional before starting, stopping, or combining supplements.

Snapshot

Evidence levelPreliminary evidence
Caution levelHigh caution
Source reviewPartially reviewed
Last reviewed2026-07-03

What this page can tell you: What the term GlyNAC means, the mechanism rationale for combining glycine and NAC, and that human evidence is early and mostly from small trials in older adults.

What it cannot: That GlyNAC slows aging or treats any condition, or that the combination is needed by the general population. There is no standardized dose or ratio.

🧩 Stack insights — how this fits into a schedule

Evidence comparisonHuman trial (RCT)

NAC (alone)GlyNAC is glycine plus NAC taken together. Compare each component alone before assuming you need the combination; the studied evidence is one trial in older adults.

Evidence comparisonHuman trial (RCT)

Glycine (alone)The glycine half of GlyNAC. In the schedule, GlyNAC is best represented as two editable items — NAC and glycine — rather than a single branded product.

Relationship insights are informational only — they describe what is commonly discussed or studied, not what you should take. Not medical advice; review your routine with a clinician or pharmacist.

NAC alone vs glycine alone vs GlyNAC (combination)

Same comparison shown on the NAC page — a discussion aid, not a recommendation.

OptionEvidence statusStudied populationsSafety cautions
NAC aloneEstablished medical uses; general supplement benefits mixed/uncertain.Broad supplemental use, less characterized.Bleeding/surgery category; asthma/bronchospasm reports; regional regulation.
Glycine aloneLimited; small sleep/relaxation studies.Small general-population studies.Generally well tolerated; review sedative/serotonergic interactions.
GlyNAC (combination)Early-stage small trials (often older adults).Older adults / specific groups.Inherits NAC cautions; no standardized dose.

Pairing and combination notes are informational — they describe what is commonly discussed or studied, not what you should take. Review combinations with a clinician or pharmacist.

📊 Studied dosing

Studied dose, not a personal recommendation. These are amounts used in specific studies or populations — not guidance for you.

InterventionDoseFormFrequencyDurationPopulationOutcome studiedSourceLimitations
Glycine + NAC (GlyNAC), combined100 mg/kg/day each of glycine and NAC (per body weight)Capsules (pharmacist-filled)Daily16 weeks (older adults); 2 weeks (younger adults)24 older adults (12 GlyNAC / 12 alanine placebo); 12 young adultsGlutathione levels, oxidative stress, mitochondrial function, inflammation, physical function markersPMID 35975308 · DOI 10.1093/gerona/glac135 (full text)Small single trial; combination design cannot separate glycine vs NAC; specific older-adult population; not a general-population or personal-dose claim.

The one combination trial reviewed for this page. Studied dose, not a personal recommendation. In a schedule, represent GlyNAC as two editable items (NAC + glycine) rather than a single branded product.

🕒 Timing

When: With a meal

Food: With or without food

Components are commonly taken together; some take NAC away from food and glycine near bedtime. Timing in trials varies.

💊 Common use range

Gram-level amounts of each component; ratios vary

No standardized combined dose or upper limit — trial protocols differ. Follow product guidance and professional input.

Ranges are informational, not a recommended dose. Talk to a professional about what is right for you.

🤔 Worth considering?

Evidence vs. effort: Uncertain — evidence unclear

An early-stage combination idea (glycine + NAC) explored in small human trials. It is not a proven protocol, and the NAC component carries bleeding/asthma cautions. Worth understanding as a concept and discussing with a professional rather than assuming it is needed.

A general summary, not a recommendation. Whether something fits your situation is worth discussing with a healthcare professional.

⚠️ Commonly noted interactions (supplements)

None listed.

Often about absorption or timing rather than danger — separating doses is common. This list is not exhaustive.

🧭 Caution level

High caution

Ask a clinician or pharmacist before use.

  • Anticoagulant (blood thinner) interaction
  • Antiplatelet interaction
  • Evidence not fully source-reviewed yet

Caution level is an informational summary of commonly discussed caution categories and doses — not a safety rating, approval, or medical advice. Low caution does not mean safe for you.

🩺 Medication caution categories

  • Blood thinners (anticoagulants)
  • Antiplatelet medication

🏥 Surgery & procedure caution

Contains NAC, which may mildly affect bleeding; share use with your care team before procedures.

If you have a procedure scheduled, bring your full supplement list to your surgical and anesthesia team. Do not stop prescribed medication unless your clinician tells you to. Do not start or stop supplements based only on this app.

✅ Quality checklist

  • Prefer products with third-party testing or a certificate of analysis (COA).
  • Check the label for the exact form and the elemental or active amount per serving.

🧩 Commonly paired with

🗣️ Questions for a professional

  • Is there any reason for me to take glycine and NAC together rather than either one, given my situation?

🛡️ Safety notes (source-reviewed)

  • Inherits NAC's cautions: bronchospasm risk in asthma, allergic reactions, bleeding/surgery category, regional regulatory status.
  • No standardized combined product, dose, or ratio — trial dosing was per body weight.

⚖️ Evidence limitations

  • Evidence reviewed here is a single small randomized trial in older adults.
  • The combination design cannot show how much glycine vs NAC contributed.
  • Not evidence for the general population, and not a claim that it slows aging or treats any condition.

❓ Frequently asked

What is GlyNAC?

GlyNAC is the name for taking glycine together with N-acetylcysteine (NAC). Both are amino-acid-related compounds the body can use toward making glutathione.

Is GlyNAC the same as NAC?

No. NAC is N-acetylcysteine on its own. GlyNAC is NAC plus glycine taken together. Some research studied the combination rather than NAC alone.

Why combine glycine with NAC?

The mechanism rationale (not an outcome claim) is that the body builds glutathione from cysteine — supplied by NAC — and glycine. Researchers studied supplying both together. Mechanism is not the same as proven benefit for an individual.

Is GlyNAC better than NAC?

The available research does not establish the combination as better for most people, or that anyone needs it. One randomized trial studied it in older adults. Whether NAC, glycine, or the combination fits your situation is a question for a clinician or pharmacist.

What has GlyNAC actually been studied for?

In a small 2023 randomized trial, the glycine + NAC combination was studied in older adults over 16 weeks, measuring glutathione, oxidative stress, mitochondrial function, inflammation, and physical-function markers. It is one early-stage trial in a specific population — not evidence for the general public.

What should someone review before adding GlyNAC?

That it is a combination concept (not a single standard product), the NAC-related cautions (bronchospasm risk in asthma, bleeding/surgery category, regional regulatory status), and — with a clinician or pharmacist — whether any of it is relevant to them. Compare NAC alone, glycine alone, and the combination first.

🔬 Evidence snapshot

GlyNAC is the combination of glycine and N-acetylcysteine (NAC), studied as a way to supply both glutathione precursors together. Human evidence is early and comes mostly from small trials in older adults and specific patient groups; it is not established for general use, and the combination is not required for everyone who takes either ingredient.

🧪 Forms & quality

Needs evidence review — no source-reviewed information yet. We only show dose and monitoring details after they have been checked against reputable sources.

See the supplement glossary for what form names like "L-", chelated, or standardized extract mean.

📏 Dose & monitoring

No established combined upper limit. Trials used gram-level amounts of each component; ratios and durations vary and are not standardized.

Evidence vs. burden: Uncertain — evidence unclear

😐 Commonly reported side effects

  • Digestive upset from either component
  • NAC-related: nausea, unpleasant smell; bronchospasm reported in some people with asthma

Non-exhaustive and individual.

🔄 Cycling & breaks

No established cycling pattern.

📅 Daily use notes

GlyNAC is a combination concept, not a single regulated product with a standard dose. If you are interested, compare NAC alone, glycine alone, and the combination, and review it with a clinician or pharmacist.

📋 Source review status

Partially reviewed — last reviewed 2026-07-03

Partially reviewed against PubMed/PMC records of small GlyNAC trials in older adults; combined dose framing kept cautious and non-prescriptive. Individual RCT details to be added to the web research notes with PMIDs.

Research backlog (queries to verify):

  • GlyNAC randomized controlled trial glutathione older adults PMID
  • glycine N-acetylcysteine combination human outcomes systematic review

📚 References

  • Kumar et al., J Gerontol A Biol Sci Med Sci 2023 (GlyNAC RCT)PubMed reviewPMID 35975308, DOI 10.1093/gerona/glac135. Full text (open access) reviewed: randomized, 24 older adults (12 GlyNAC / 12 isonitrogenous-alanine placebo) for 16 weeks, plus 12 young adults for 2 weeks; dose 100 mg/kg/day EACH of glycine and NAC in capsules. Small single trial; combination design cannot separate glycine vs NAC contributions. Cited to characterize the combination as early-stage in a specific population, NOT to claim general benefit.
  • MedlinePlus — Acetylcysteine (NAC) safetyMedlinePlusUsed for the NAC component's safety notes (bronchospasm/asthma risk, allergic reactions). Covers the medication; supplemental-context wording kept cautious.

Verified against the source shown. See the research-status page for how review works.

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Not medical advice. SuppSafety and StackWise are informational research and tracking tools. They are not medical advice and do not diagnose, treat, cure, or prevent any condition. Supplement research is often limited or mixed, and individual needs vary. Always talk to a qualified healthcare professional before starting, stopping, or combining supplements — especially if you take medication, have a health condition, are pregnant or breastfeeding, or have a procedure scheduled.