Doctor's Best Glucosamine Chondroitin MSM + Hyaluronic acid provides four important nutrients which help maintain healthy joints: Glucosamine, Chondroitin, methylsulfonylmethane (MSM, from optimal), and hyaluronic acid (from Bio cell collagen).* Glucosamine Sulfate helps promote joint lubrication for better joint movement and flexibility.* MSM supplies bioavailable sulfur needed for joint health. Biocell Collagen is a proven dietary ingredient that contains a patented composition of naturally occurring hydrolyzed collagen Type II, Chondroitin sulfate, and hyaluronic acid in a highly absorbable Matrix.*