Glycine: A Foundational Molecule in Human Health Glycine is the simplest amino acid, yet it plays essential roles in sleep, detoxification, glutathione synthesis, collagen production, creatine synthesis, and neurotransmission Research suggests that 3 grams of glycine taken before bed may activate receptors in the brain's master clock, associated with peripheral vasodilation and a drop in core body temperature that supports sleep onset Glycine is the rate-limiting amino acid for glutathione, one of the body's key intracellular antioxidants; supplementing it with NAC has been associated with improvements in multiple hallmarks of aging The classification of glycine as "non-essential" may be scientifically incomplete and has led to decades of neglect of this foundational nutrient Research suggests glycine may enhance exercise performance, reduce lactic acidaccumulation, and support muscle recovery, pointing to a potential ergogenic role