Glycine is a the smallest and simplest amino acid, making it versatile for use in a wide range of functions. Glycine is necessary for the production of proteins, glutathione, DNA, creatine, bile, hemoglobin, and most proteins. It also helps to promote glycogen storage, thereby making glucose readily available for energy production. Glycine also functions as a calming neurotransmitter in the brain, where it facilitates nerve impulses and is important for the maintenance of healthy sleep patters.