The Relationship Between Oxidative Stress, Selenium, and Cumulative Risk in Metabolic Syndrome In Vivo Is glutathione safe? Because glutathione levels decline as you age, and glycine can help slow the glutathione slide, it's a good idea to keep your levels high by eating protein rich foods, like organic poultry, grass fed Glutathione is often called the body's master antioxidant, but most people don't really understand what it does. It plays a central role in protecting your cells from damage, supporting detox pathways, and