NOW Liquid Glucosamine & Chondroitin with MSM combines three of the best known nutrients available for the support of healthy joints in a convenient liquid form. Scientific studies have demonstrated that Glucosamine and Chondroitin can promote normal joint mobility and comfort. MSM is present as a naturally occurring sulfur compound and Manganese and Vitamin C have been included as complementary ingredients to provide optimal nutritional support for the production of healthy joint structures. NOW Foods developed the glucosamine test method chosen as the official AOACI industry standard method. Natural color variation may occur in this product.