Assessment of red blood cell glutathione status in insulin resistance PDF] Blood glutathione concentrations in a large scale human study. Semantic Scholar 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, Glutathione: Master Antioxidant, Reducing Oxidative Stress, and Detoxification Glutathione Benefits for Gut Health Nikki Yelton RD