Gl
Glutathione
GlutathioneAntioxidant
Endogenous antioxidant tripeptide. Topical brightening evidence is weak compared to oral supplementation studies.
What it does
Glutathione is the body's primary intracellular antioxidant. Topically it's marketed for brightening and pigmentation evening, but most peer-reviewed evidence comes from oral or IV supplementation in clinical contexts (which has its own concerns). Topical penetration of glutathione is poor without specialized delivery systems. The marketing often runs ahead of the cosmetic-formulation evidence.
Also known as
gsh, l-glutathione
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