Glutathione (GSH)

Glutathione is a 6.0–6.5/10, worth trying for the right person and easy to overrate for everyone else. The practical verdict is to treat it as a targeted, tracked experiment rather than a blanket wellness staple. The people most likely to benefit are those with measured glutathione depletion, fatty liver, or a high oxidative-stress burden who will pick an absorbable route and watch a specific marker. The people most likely to waste money are healthy users swallowing plain capsules expecting dramatic effects, and anyone chasing skin whitening, where the evidence is weak and the injectable route is dangerous. The score tier is justified by a foundational mechanism and excellent safety pulling up against modest, mixed clinical outcomes and a cheaper precursor alternative pulling down.

✅ Best for: Adults with documented glutathione depletion or high oxidative-stress burden who will track a redox or inflammatory marker; people with non-alcoholic fatty liver disease willing to monitor ALT over 3 to 4 months, the population with the clearest signal in Honda 2017; older adults exploring the aging-redox angle who understand the strongest data is for the GlyNAC precursor; experimenters willing to use a sublingual or liposomal form rather than plain capsules to overcome poor absorption; anyone who would otherwise reach for an unproven antioxidant and prefers a benign, well-understood molecule with a clean stop.

❌ Avoid if: You expect a dramatic acute effect, because oral glutathione works slowly and subtly; you are pursuing skin lightening, where the oral evidence missed significance and the injectable route is unapproved and linked to Stevens-Johnson syndrome and contamination; you would source injectable glutathione from a non-medical or skin-whitening clinic, the one genuinely risky path; you want the most cost-effective way to raise glutathione, in which case N-acetylcysteine is the better-evidenced and cheaper precursor; or you are already well-nourished and antioxidant-replete and would notice nothing.