Glutathione is such a critical soldier in our line of defense that our bodies make it themselves. We even have mechanisms that recycle and reuse it. But what happens when our toxic Glutathione is a natural antioxidant your body makes, and it can influence melanin production which is why its sometimes marketed for skin brightening., Oral supplements are mostly broken down in How Do Glutathione Injections Work Inside the Body? Glutathione vs. NAC: Which Antioxidant Is Best for Your Liver? Life Extension