L-Glycine

Glycine is the smallest amino acid and is considered non-essential, meaning the body can produce it, though it is also obtained from foods. It plays a key role in building proteins—especially collagen, which supports skin, joints, and connective tissues—and functions as an inhibitory neurotransmitter in the brain, helping promote relaxation and better sleep. Glycine is also involved in important metabolic processes, including detoxification in the liver and the production of compounds like glutathione (a major antioxidant), creatine, and heme for red blood cells. It is found in protein-rich foods, particularly collagen-rich sources like bone broth and gelatin, as well as meat, fish, dairy, and legumes. Supplementation is generally safe in moderate doses and may support sleep quality, recovery, and overall health.