Ingredient glossary
Glutathione
On your shelf ✓What Glutathione does for your skin, who it suits, and what to watch for.
INCI: Glutathione · Also: Reduced Glutathione, GSH
In short: Glutathione delivers antioxidant and brightening, suits most skin types, and the evidence behind it is moderate. One thing to know: clear it with your doctor if pregnant.
- What it does
- Antioxidant, brightening
- Best for
- Most skin types
- Watch out
- Clear it with your doctor if pregnant
- Evidence
- Moderate
- How long
- Under 2 weeks
The molecule
The Glow take
Genuinely worth a spot in your routine.
When your goal is fading dark spots and evening out tone, Glutathione pulls genuine weight, with a solid amount of evidence behind it. Gentle enough that most skin types can reach for it.
— Maya
What it does
- antioxidant
- brightening
moderate evidenceSystematic reviews and small RCTs indicate that topical two percent oxidized glutathione and oral five hundred milligram dosing can reduce melanin index and improve some aging markers in sun exposed skin but data quality and consistency are limited.
On a label: usually effective at 2%.
Who it's for, and who should skip it
Tends to suit
- pigmentation
- photoaged
- normal
- combo
Approach with care
No specific group flagged to avoid it.
- Clogs poresLow
- Irritation riskLow
How it fits each skin type
- DrySuits
- CombinationSuits
- OilySuits
- SensitiveSuits
Often chosen for pigmentation, photoaged.
Where it fits in your routine
Give it under two weeks — that is when the change first became measurable.
What was measured, and in whom
Measured on: Melanin index of facial skin, Mexameter reading on the treated half-face versus placebo.
The trial measured the melanin index at baseline and then weekly for ten weeks (days 7 through 70), and the treated side sat significantly below placebo from week 1 onward, not at the endpoint alone — so the earliest visit that separated is day 7 and the 10-week figure is the last visit, not the first. Read week 1 as an upper bound on onset rather than as demonstrated depigmentation: epidermal melanin turnover cannot produce real pigment loss in seven days, so much of the day-7 gap is likely the lotion's optical and hydration effect on the reading, with the durable component being whatever persists to week 10. The other endpoints are genuinely slower and separated only late — smoothness weeks 6-10, wrinkle curvature weeks 6 and 10, stratum corneum moisture weeks 8-9, elasticity never. Two limits stand: the material is 2% oxidized glutathione (GSSG), not the reduced GSH most consumer products list, and every author except the contract research site was employed by the glutathione manufacturer, with no independent replication. Oral 500 mg data is a separate literature and does not describe a topical timeline.
Watanabe F, Hashizume E, Chan GP, Kamimura A. Skin-whitening and skin-condition-improving effects of topical oxidized glutathione: a double-blind and placebo-controlled clinical trial in healthy women. Clin Cosmet Investig Dermatol 2014;7:267-274. PMID:25378941 (30 healthy women, 2% w/w GSSG lotion split-face vs placebo twice daily, melanin index read weekly to week 10).
Plays well with
- vitamin c
- niacinamide
- other brighteners
Glutathione, answered
Is Glutathione safe during pregnancy?
Clear it with your doctor first. Glutathione is flagged as use-with-caution during pregnancy and breastfeeding, so check with your doctor or midwife before adding it.
Who should avoid Glutathione?
No specific group is flagged to avoid Glutathione. It is well tolerated by most skin. Still, introduce anything new one product at a time.
What concentration of Glutathione actually works?
Glutathione tends to be effective at around 2%. Much lower and it is likely underdosed.
During pregnancy
Treat Glutathione as a maybe rather than a yes for now. It is flagged as one to use with caution while pregnant or breastfeeding, so it is worth clearing before you carry on.
When in doubt, check with your doctor or midwife. They outrank any website, including this one.When it is worth booking →
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