Glucosamine is naturally found in joint tissue and is a key structural component in cartilage. Chondroitin is a naturally occurring compound that is a building block for connective tissues, including joint cartilage. Methylsulfonylmethane (MSM) is a source of dietary sulfur, a trace element used by the body in collagen, connective tissue, and joint cartilage. These ingredients are commonly found in joint support supplements.†