26/01/2026
If aging is driven in part by declining glutathione, mitochondrial dysfunction, and chronic inflammation, can restoring the raw materials reverse some of that biology?
A controlled clinical trial tested a simple combination: glycine + N-acetylcysteine (NAC) in older adults. The goal wasn’t symptom relief, it was to target core mechanisms of aging.
What the study found:
- Aging adults had low glutathione, impaired mitochondrial fuel use, and elevated oxidative stress.
- Supplementing glycine + NAC restored glutathione levels toward youthful ranges.
- This was accompanied by improvements in mitochondrial function, oxidative stress markers, insulin resistance, inflammation, and muscle strength.
- Several abnormalities moved toward values seen in young adults, not just modest improvements.
Why glycine + NAC together matters
- NAC supplies cysteine — the rate-limiting precursor for glutathione.
- Glycine is also required to complete glutathione synthesis.
- Providing only one leaves glutathione synthesis constrained. The combination removes both bottlenecks.
Protocol used in the study (not medical advice):
- Glycine: ~100 mg/kg/day
- NAC: ~100 mg/kg/day
- Divided doses, daily, over multiple weeks
This wasn’t an antioxidant band-aid. It was a substrate-repletion strategy that corrected multiple aging-related defects at once — energy metabolism, redox balance, inflammation, and physical function.
Sometimes the most powerful interventions aren’t exotic. They’re mechanistically correct.
