Dark spots have always been my skin struggle, but the No.5 Glutathione Serum truly helped. With Glutathione, Niacinamide & TXA, it helps brighten skin, fade dark spots, and even out skin tone. Page 1 Reviews Numbuzin, No.5 Glutathione Vitamin Concentrated Serum, 1.01 fl oz (30 ml) iHerb Glutone A with Japanese L Glutathione+Tablets Glutathione as a skin whitening agent: Facts, myths, evidence and controversies Indian Journal of Dermatology, Venereology and Leprology Numbuzin No.5 Vitamin Concentrated Serum numbuzin No.5+ Vitamin Concentrated Serum (Glutathione + Vitamin Boosting Serum) Suitable For: Dull & tired skin Uneven skin tone Pigmented dark spot prone skin Normal, dry