MSM from Jarrow Formulas contains is an organic sulfur compound of natural MSM (methyl-sulfonyl-methane) found in animal tissues. It is one of the main building blocks of glycosamineoglycans which are key structural components in cartilage. It is present in small amounts in many foods and drinks and is often used in combination with Glucosamine and / or Chondroitin. Jarrow Formulas MSM is an organic source of bioavailable sulfur. Sulfur is an antioxidant mineral found in major structural tissues of the body such as cartilage. The sulfur from MSM is used to produce glycosaminoglycans (or mucopolysaccharides) present in proteoglycans, such as chondroitin sulfate, dermatan sulfate and hyaluronic acid. These sulfur-containing glycosaminoglycans are found in high concentrations in connective tissues, including joint cartilage, skin and collagen. For best results, use with Jarrow Formulas JarroSil, the biologically Activated Silicon.