Seven Seas JointCare contains key ingredients for 4-in-1 joint support1-4, to help you maintain an active lifestyle. It supports 4 important components of your joints. (1) Bones: Vitamin D & Zinc contribute to the maintenance of normal bones. (2) Muscles: Vitamin D contributes to the maintenance of normal muscle function. (3) Cartilage: Vitamin C contributes to normal collagen formation for the normal function of bones & cartilage. (4) Connective tissue: Manganese contributes to the normal formation of connective tissue.