Lysine, also called L-lysine, is an amino acid that is necessary for many bodily functions. Lysine is an amino acid building block of protein. People use it to make medicine. Lysine is used for preventing and treating cold sores.

It also helps your body better absorb calcium for bone health. Lysine may also treat cold sores. Studies show that Lysine helps build collagen in the skin. Getting adequate amounts of amino acids, including lysine, along with other healthy nutrients may contribute to overall skin health. Lysine supplementation with its numerous health benefits may be useful in dealing with aging and slowing that process. This natural supplement may improve hair appearance, smooth the skin, reduce wrinkles. Lysine is an α-amino acid that is used in the biosynthesis of proteins.