With Manganese and Vitamin C Supports Joint Health Dietary SupplementGlucosamine and chondroitin sulfate are fundamental component of joint tissue involved in the production of hyaluronic acid, which is an important component of the synovial fluid that lubricates the joints and a major component of the connective tissue in the skin.Vitamin C and manganese are required for the synthesis of collagen and cartilage.Jarrow formulas glucosamine sulfate is sodium free and stabilized with potassium chloride (KCI).