Supplement analysis backed by scientific evidence · PT

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Limited evidenceLongevity & antioxidants

S-Acetyl Glutathione

An acetylated glutathione claimed to survive digestion better than the plain form. Safety has been assessed, but no trial has shown it outperforms ordinary oral glutathione or produces a clinical benefit.

Evidence last reviewed: August 2026

What the science says

  • Raising body glutathione stores Limited evidence

    A randomized controlled trial of plain oral glutathione (250 or 1,000 mg/day for six months) did increase glutathione in blood, erythrocytes and buccal cells, contradicting the claim that oral glutathione is entirely destroyed in the gut. That trial did not test the S-acetyl form, and no equivalent trial of S-acetyl glutathione has been published.

  • Superior absorption of the acetylated form Limited evidence

    The advantage of S-acetyl glutathione rests on pharmacokinetic reasoning and cell work rather than head-to-head human comparisons. A published safety assessment characterizes the ingredient for food use but does not demonstrate better bioavailability or any clinical outcome.

Dosage & safety

Studied doseNo efficacy-based dose. Products typically supply 100–300 mg/day; the plain glutathione trial used 250–1,000 mg/day.
SafetyA formal safety assessment supports use in foods and supplements at typical intakes, and plain oral glutathione was well tolerated over six months. Mild gastrointestinal upset is the main reported complaint. Not studied in pregnancy, breastfeeding or children; people on chemotherapy should ask their oncologist before taking antioxidant supplements.

Scientific references

Where to buy

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