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 Unveiling the Role of Glutathione S transferase Protein in Breast Cancer Drug Resistance: Insights into the Signaling Pathways and Therapeutic Implications ACS Pharmacology & Translational Science GPX1 (Glutathione Peroxidase, GSHPx) Gene Variants and Cardiovascular Revolution Health & Wellness Glutathione S transferase: A keystone in Parkinson's disease pathogenesis and therapy ScienceDirect