Holland & Barrett High Strength Glucosamine & Chondroitin Caplets, A high strength blend of Glucosamine and Chondroitin with MSM. Glucosamine and Chondroitin are naturally found in the joints of the body. Rarely found in natural food sources, Glucosamine is a building block of cartilage and joint tissue. It is the basis of the synthesis of several important macromolecules including glycoproteins, glycolipids and glycosaminoglycans.