Glycine + NAC
Can you take Glycine and NAC together?
Yes — this is the “GlyNAC” combination, tested in small trials in older adults.
What to do. They don't need to be taken at the same time. Note that the trial dose is about 7 g of each for a 70 kg adult — far more than typical capsules — and whether lower doses help is unknown. The trials were small and came from one research group.
Mechanism
GlyNAC: glycine + NAC to rebuild glutathione
Glutathione, the main antioxidant inside cells, is built from cysteine, glycine and glutamate, and older adults often run low on the first two. In a 16-week placebo-controlled trial in 24 older adults, glycine and NAC at 100 mg/kg/day each restored glutathione and improved oxidative stress, insulin resistance and physical function.
Evidence: Strong evidence — Randomized trials, meta-analyses or clinical guidance that directly support this specific claim.
- 01Kumar P et al. Supplementing glycine and N-acetylcysteine (GlyNAC) in older adults improves glutathione deficiency, oxidative stress, mitochondrial dysfunction, inflammation, physical function, and aging hallmarks: a randomized clinical trial. J Gerontol A Biol Sci Med Sci 2023.
- 02Kumar P et al. Glycine and N-acetylcysteine (GlyNAC) supplementation in older adults improves glutathione deficiency, oxidative stress, mitochondrial dysfunction, inflammation, insulin resistance, endothelial dysfunction, genotoxicity, muscle strength, and cognition: results of a pilot clinical trial. Clin Transl Med 2021.
Timing
A day with Glycine and NAC
- 07:00
On waking
no food - 22:30
Bedtime
no food
Taking more than these two?
Add the rest of your stack and your medications for a complete check.
Buying guide
What to look for on the label
Glycine
- Glycine powder (slightly sweet, dissolves in water)
NAC
- Capsules in sealed blister packs or with desiccant (NAC oxidizes)
Learn more about Glycine and NAC