L-Proline, an essential amino acid, is a precursor, along with vitamin C, of collagen. Collagen is a building block of tendons, ligaments, arteries, veins and muscles--the heart muscle in particular; collagen also helps heal cartilage, and cushions joints and vertebrae.

L-Proline is important in wound healing, cartilage building, and in flexible joints and muscle support. It also helps reduce the sagging, wrinkling, and aging of skin resulting from exposure to the sun.

L-Proline, by breaking down protein, helps create healthy cells. It is essential both to skin health, and for the creation of healthy connective tissues and also muscular tissue maintenance.