Keep your joints working smoothly with NOW® Liquid Hyaluronic Acid! Hyaluronic Acid is a lubricant present in every tissue of the body, with the highest concentrations occurring in connective tissues such as skin and cartilage. As a constituent of joint fluid, hyaluronic acid also supports joint health and plays a role in resetting compressive forces. This formula from NOW combines this essential component with vitamin D and other nutrients that are essential for the formation of collagen found in cartilage and connective tissue to support optimal joint health.