TWO INGREDIENTS. AN OPEN BOOK.
Understand GlyNAC in plain English, see the research, and decide if it fits your goals.
Ask our AI chatbot about studies, ingredients or labels. Answers include sources.
01 — START WITH THE BAYLOR STUDY
In Baylor’s small 16-week trial, the GlyNAC group improved glutathione, walking speed and grip strength. Here’s what the researchers tested.
In this 16-week trial of adults aged 61–80, the GlyNAC group improved muscle glutathione, walking speed and grip strength.
Small, selected groups and many measurements: these findings do not establish a benefit for everyone or longer human lifespan.
The wider picture: a separate, larger two-week trial did not improve its main blood-glutathione measure. Differences in participants, duration and protocol matter. These studies do not establish the effectiveness of a retail product.
ONE MEASUREMENT AT A TIME
Read short explanations of glutathione, oxidative stress, inflammation and physical function, with the actual comparison groups.
02 — THE IDEA
Glutathione helps cells manage oxidative stress. GlyNAC combines glycine with a source of cysteine—two of the building blocks used to make it.
Glycine is an amino acid and one of the three components of glutathione. The combination with NAC is what these GlyNAC studies tested.
Simplified pathway. Glutamate is the third component; individual responses vary.
03 — THE AMOUNTS
A capsule, a serving and a full day can mean different amounts. Compare glycine and NAC separately, using the actual directions.
Three ways to read the amounts: a weight-based research protocol, fixed trial benchmarks, and actual bottle directions. These are comparisons, not three recommended plans.
TIER 1 · HUMAN GLYNAC TRIAL
100 mg/kg/day each of glycine and NAC, studied for 16 weeks in selected adults aged 61–80.
The slider illustrates the published formula. Fractional capsule equivalents are math, not directions to take or divide capsules. This trial did not determine a minimum or optimal dose.
Baylor trial ↗TIER 2 · HUMAN DOSE-RANGING TRIAL
Glycine + NAC per day, split morning/evening in the separate Lizzo et al. 2022 study. 117 older adults were randomized; 114 completed two weeks.
The primary whole-blood glutathione outcome did not significantly improve. These are tested amounts, not a ranking of effective doses.
It was the middle amount of each ingredient in Lizzo’s trial. In a different, NAC-only lupus pilot, all nine active recipients at 2.4 g/day completed treatment; the 4.8 g/day tier had three intolerance cases, including GI symptoms and headaches. That does not establish a universal mTOR threshold or a GlyNAC safety ceiling.
Read the lupus study context ↗TIER 3 · PRODUCT-SPECIFIC LABELS
Checked examples, not an estimate of what is typical across the market. Canadian NPN directions vary by product.
NOW’s US glycine label ↗ instead lists 1–3 g/day. Country-specific directions matter. Check the current bottle; these examples are not selected recommendations.
Format affects convenience: gram amounts can mean many capsules. Glycine powder can reduce capsule count; compare the measured grams, ingredients, testing information and cost per gram. Explore ingredient formats ↗
EACH INGREDIENT, PER DAY
14×The trial example supplies fourteen times this selected product’s labelled daily amount of each ingredient.
| Product / original label | Suggested use | Glycine | NAC | Source note |
|---|---|---|---|---|
| WeBotanix · GlyNAC Formula ↗ | 2 capsules daily | 500 mg | 500 mg | Amounts follow the two-capsule table and directions; the advertised bottle duration conflicts. |
| Youth & Earth · GLYNAC ↗ | 2 capsules daily | 500 mg | 500 mg | Amounts come from the detailed two-capsule composition. |
| SuperSmart · GlyNAC ↗ | 2 capsules daily | 600 mg | 600 mg | US-facing product page; 300 mg of each per capsule. |
| Purovitalis · GlyNAC Clarity ↗ | 2 capsules daily on current product page | 600 mg | 600 mg | Product page says two daily; a help article instead says one. Directions disagree. |
| vitalityPRO · GlyNAC ↗ | 2-3 capsules daily | 700–1,050 mg | 700–1,050 mg | Range reflects two to three capsules; this is not Vitality Supplements. |
| Utzy Naturals · GlyNAC+ ↗ | 3 capsules daily | 1,000 mg | 1,000 mg | Additional vitamin B2 is not counted here. |
| BioStack · GlyNAC+ ↗ | 6 capsules on use days; cycle 5 days on and 2 off | 3,000 mg | 1,200 mg | Use-day amounts only: five days on, two off. Additional ingredients excluded. |
| Pure Encapsulations · NAC + Glycine Powder ↗ | 1 scoop daily | 1,800 mg | 1,800 mg | US directions. Canadian directions and availability are unverified. |
This small convenience sample includes US, UK and European pages. It does not establish what is typical in the market, ingredient potency, Canadian authorization, shipping eligibility or efficacy. Other ingredients are excluded from these amounts. Label directions can change; check the current bottle before relying on them. Products here are examples, not selected recommendations or affiliate endorsements.
Download the comparison data ↓05 — BUILD YOUR SHORTLIST
GlyNAC describes a combination of two ingredients.
Compare each on its own terms.
A straightforward way to compare glycine by the gram. Look at ingredient purity, serving size, testing information and value.
The cysteine source in GlyNAC. Compare formats and label amounts carefully; a retail serving is not automatically a study dose.
The studies used specific formulations and protocols. The comparison describes research and labels; it does not select a dose for you. Discuss suitability and medication interactions with your doctor or pharmacist.
06 — THE STANDARD
MICHAEL
PROJECT CREATOR
“GlyNAC is the one I keep coming back to—super underrated, in my opinion.”
This started with personal curiosity about supplements. The standard is simple: make the research readable, show the limitations, and let people make a more informed choice.
The original paper is one click away.
Clear sources, with study design and context.
The inconvenient result belongs here too.
A less positive study is part of the story.
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GlyNAC is the combination of glycine and N-acetylcysteine (NAC). They supply precursors used in glutathione synthesis. GlyNAC describes this combination of ingredients; formulations and serving amounts vary between products.
No. Findings come from specific groups, including older adults, and study designs and durations differ. Small samples, limited independent replication and a less positive randomized trial leave important questions open.
This guide doesn’t recommend a personal dose. Study protocols and retail serving sizes can differ substantially. Bring the product label and the research to your doctor or pharmacist to discuss whether it is suitable for you.
That needs an individual assessment. Supplements can have side effects and interact with medication. A pharmacist or clinician can review your medicines, health history and the exact product before you start.
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Protocol N°1 is the umbrella concept behind this independent guide: supplements explored through human research, with sources and limitations in plain sight. GlyNAC is the first field guide.
KNOW WHAT YOU’RE CHOOSING.