L-tyrosine is an alpha amino acid that is used as a building block during the production of proteins. It is considered to be a non-essential amino acid, which means it can be synthesized by the human body under normal physiological circumstances. Specifically, the body can synthesize L-tyrosine from phenylalanine, another type of amino acid. Tyrosine can also be found in a variety of high protein foods.

Topical application of L-tyrosine can assist the skin in making important proteins, such as collagen and elastin. Collagen is important for skin strength, while elastin is important for skin elasticity. Both collagen and elastin levels in the skin decrease with age. The skin needs amino acids like L-tyrosine to generate these proteins and new skin cells. Deficiency in essential amino acids will result in skin that appears visibly dry and thin. Therefore, topical application of ingredients that stimulate the production of collagen and elastin, such as L-tyrosine, may help to decrease signs of aging and improve the overall appearance of skin. L-tyrosine also improves skin hydration because amino acids work together with aquaporins (the body’s water transport system) to move moisture throughout skin.