Source Naturals Glucosamine Chondroitin Complex with MSM provides four important building blocks for healthy joints and connective tissues: glucosamine, chondroitin, bioavailable sulfur (MSM), and vitamin C. Glucosamine, an amino sugar, is an essential structural component of glycosaminoglycans, large linear molecules that help to lubricate joints, nourish cartilage and connective tissue, and assist in wound healing. Chondroitin sulfate lends additional structural support via its high degree of interaction with collagen fibers. Bioavailable sulfur (MSM) plays a critical role in the integrity of joints and connective tissues. Vitamin C, essential for the production of collagen, also serves as an effective free radical scavenger to protect cells. Molybdenum aids in complete metabolism of MSM, glucosamine, and chondroitin.