What the studies show
Oral 500 mg/day and topical 2% oxidised glutathione reduced the melanin index in sun-exposed skin; no effect was seen in sun-protected skin. Reviewers judged the overall evidence inconclusive.
“Current evidence of the skin whitening effect of glutathione is still inconclusive due to the quality of included studies and inconsistent findings.”
A few small or poorly-controlled human studies. Enough to be interesting; not enough to count on. Most of what gets called “clinically proven” online lives here.
- 1Dilokthornsakul W, et al. The clinical effect of glutathione on skin color and other related skin conditions: a systematic review.J Cosmet Dermatol, 2019;18:728–7374 studies; conclusion inconclusive.
In context
Glutathione is a three-amino-acid molecule every cell makes and uses to handle oxidative stress. It is sold orally and, in some countries, intravenously for skin lightening. Systematic reviews of the small trials find it may brighten sun-exposed skin slightly, but call the evidence inconclusive because the studies are few, small and inconsistent. Oral absorption is itself questionable, and the intravenous use that carries the most risk has the least evidence — in 2026 the FDA linked at least 30 adverse events, some needing hospital care, to injectables compounded from supplement-grade glutathione contaminated with endotoxin.
Glutathione is supplement; injectable use unapproved. Legal status differs by country — see the regulation section or the jurisdiction pages.
Questions
Is Glutathione proven to help with skin lightening?
What studies are behind the grade?
Is Glutathione approved for this?
Other outcomes for Glutathione
- COral bioavailabilityadverseReviews
- DIntravenous use for skinNo adequate controlled trial
- BEndotoxin reactions from compounded injectablesadverseFDA case series (≥30 patients); recalls
- CSafety (oral, short-term)adverseSmall trials
Written and maintained by LYO Research — how pages are written and checked. Reviewed 7 October 2026. Grades count human evidence only; see how LYO grades. Not medical advice. Correct this page →