The most abundant mucopolysaccharide in the body. It is synthesized in significant amounts but the concentration declines with the normal aging process. It acts as the flexible connecting matrix between tough protein filaments in cartilage to form a polymeric system similar to reinforced rubber. It makes up many body tissues including cartilage, tendons, ligaments, skin, mucus and structures in the eyes. Along with regular exercise, chondroitin sulfate and certain other dietary ingredients may be helpful in maintaining joint health.