N-acetyl glucosamine (NAG) lightens skin by inhibiting the glycosylation of tyrosinase.
NAG (3%) applied topically to skin equivalent cell cultures significantly inhibits melanin
content in a dose-dependent manner. Clinically, treatment with a 4% niacinamide
plus 2% NAG combination for 8 weeks was significantly more effective at reducing
hyperpigmentation than niacinamide alone.