With Undenatured Type II Collagen Plus Hyaluronic Acid, Boron, Vitamin D-3 Promote optimal joint health and mobility with Advanced UC-II Joint Relief, featuring UC-II, a patented form of collagen with undenatured type II collagen. Undenatured type II collagen is the principal structural protein in cartilage that gives it tensile strength and toughness. It works with the immune system to support healthy joints by ensuring an adequate supply of collagen that’s easily used by the body. Human clinical studies show that just one 40 mg capsule of UC-II per day can help promote joint function, flexibility and comfort. We’ve included hyaluronic acid and boron for their complementary roles in overall joint health.