Tendons, ligaments, intervertebral disc and articular cartilage in joints provide movement, stability and shock absorption for the body. Joint nutritional supplements may help prevent deterioration, improve flexibility and decrease pain. Glucosamine sulfate is an essential component of joint cartilage and joint fluid. It functions to give strength to joint cartilage and improve shock absorption. Studies suggest that taking glucosamine may decrease reliance on anti-inflammatory pain medications.