L Glutathione vs. oxidized vs. Reduced Glutathione Glutathione, often dubbed the master antioxidant plays a crucial role in detoxification, immune function, and protecting our cells from oxidative stress. Here are some signs that your levels might be low: Persistent The antioxidant glutathione ScienceDirect How to Take Glutathione Effectively: Dosage & Tips Glutathione is the body's primary internal antioxidant, made using the amino acid cysteine, and it helps protect cells from oxidative stress. Beyond detoxification, research shows glutathione is involved in thyroid hormone metabolism, What is glutathione and why must we protect patient access to it?