glutathione makes me darkyoutubeer Doctor V - Is safe? | Skin Of Colour | Brown Or Black Skin The only video you need
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Safe for sensitive skin, it deep-cleans pores, brightens your complexion, and helps control breakouts using three different serums

Further studies are needed to precisely determine the appropriate dose of NAC for these cases
doi: 10.1126/science.287.5457.1497

At present, there is no definitive cure that permanently restores pigment in every patient