Glucosamine sulfate (GS) supports joint function by supplying the body with dietary ingredients (glucosamine and sulfur) for manufacturing proteoglycans in healthy joints. Glucosamine, an amino sugar that is essential to the glycosaminoglycans found in cartilage and synovial fluid, stimulates chondrocytes (cartilage cells) to manufacture proteoglycans. Proteoglycans contribute to the maintenance of sound joint structure, ultimately enhancing healthy joint function. Additionally, glucosamine inhibits unhelpful catabolic enzymes and can aid in the balance of interleukin-1 levels in synovial fluid. A recent in vitro investigation examining the molecular biology of chondrocytes found 18 different proteins that were modulated by glucosamine sulfate. In conjunction with other studies, this new evidence suggests that GS fights cytokine-mediated oxidative stress in chondrocytes. Sulfur is a mineral that maintains the structural stability and strength of various tissues by forming sulfur “tie-bars” (sulfhydryl bonds) between connective tissue proteins. MSM supplies the body with nature’s primary source of organic bioavailable sulfur. Vitamin C is required for reactions that occur during the production of collagen, an important component of joints, tendons, and skin. An adequate supply of Vitamin C enhances the normal maintenance of these structures. Vitamin C is essential for production of collagen, a protein that supports joint health.