Glutathione vs NAC (N-Acetylcysteine)
Swallow the antioxidant itself, or the precursor that lets you build it. Oral glutathione raises body stores; NAC's real credentials are medical, not the daily antioxidant capsule.
Glutathione
GSH
Oral glutathione raises body stores in a 6-month RCT (reverses on stopping); but longevity/detox claims are unproven, skin-lightening is modest, and IV is the least-evidenced route.
Full Glutathione evidence reviewNAC (N-Acetylcysteine)
A cysteine/glutathione precursor that is genuinely strong for specific medical uses (acetaminophen-overdose antidote, some psychiatry) but weak as an everyday 'antioxidant/detox' pill.
Full NAC (N-Acetylcysteine) evidence reviewSide by side
| Glutathione | NAC (N-Acetylcysteine) | |
|---|---|---|
| Marketed for | Antioxidant, detox, anti-aging, skin | Antioxidant, detox |
| Evidence grade | Clinical data | Clinical data |
| Family | NAD⁺ & mitochondrial | NAD⁺ & mitochondrial |
| Key human source | Oral RCT, Eur J Nutr 2015 | Acetaminophen antidote, NEJM 2008 |
marks a row where the two differ. Evidence grades come from our evidence matrix, which grades each molecule on the human data for the use it is marketed for.
Our verdict
Both feed the same system, and neither has human outcome data for aging. Oral glutathione raised body stores dose-dependently in a 6-month randomized trial, but levels drifted back toward baseline about a month after stopping, and the trial measured biomarkers rather than disease. NAC's strongest evidence is medical rather than wellness: it is the FDA-approved hospital-standard antidote for acetaminophen overdose, with narrower support in some psychiatry, as a respiratory mucolytic and for male fertility, while the everyday antioxidant and detox use it is mostly bought for is the thinnest part of its record. Because cysteine availability is the rate-limiting step in making your own glutathione, the precursor route is the more mechanistically rational one; IV glutathione is the least-evidenced form of either.
Glutathione fits if
Someone who specifically wants to raise measured glutathione stores with an oral course and understands the gain reverses once they stop.
NAC (N-Acetylcysteine) fits if
Someone who wants the cheaper precursor with a genuine pharmacological track record, and who is clear that the antidote and psychiatry data do not transfer to a daily anti-aging pill.