6 health benefits of glutathione 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, Assessment of red blood cell glutathione status in insulin resistance Glutathione Benefits for Gut Health Nikki Yelton RD