Glycine + NAC
With meals
Glycine and N-acetyl cysteine (NAC) are two amino acids that together provide the essential building blocks for glutathione, the body's primary endogenous antioxidant. Glutathione production naturally declines with aging, particularly after midlife, and supplementing with its direct precursors can help restore levels more effectively than taking glutathione itself, which is poorly absorbed orally. This combination has emerged from clinical research on aging biology and is increasingly studied for its effects on oxidative stress and mitochondrial health.
Research Evidence
Reduces markers of oxidative stress
ModerateRestores glutathione levels in older adults
ModerateMay improve markers associated with age-related decline
LimitedProvides glutathione precursors more effectively than oral glutathione
ModerateSupports mitochondrial function in aging
LimitedExpert Evidence
4 references from 1 expert
2026
2024
2022
Safety & Cautions
Side Effects
- Nausea or GI discomfort from NAC
- Sulfurous taste or smell from NAC
- Mild bloating at higher doses
- Rare headache
This combination is generally well-tolerated at studied doses, though NAC can cause gastrointestinal upset in some individuals, particularly at higher intakes. Those on blood-thinning medications or with bleeding disorders should consult a physician before supplementing with NAC, as it may have mild anticoagulant properties.
Pairs Well With