Pro Bones contains all of the essential nutrients required for building healthy bones, including calcium, vitamin D, and magnesium. Pro Bones can benefit bone and joint health in those with or who are at risk of osteopenia, osteoporosis, and arthritis. Pro Bones increases bone mass, improves bone growth quality, and reduces the risk of fractures. As a superior source of calcium, MCHC can slow bone loss and actually reverse it. Manganese is included to ensure the proper function of osteoblasts, vitamin K to regulate calcium and keep it within the bone, and glucosamine for joint and cartilage repair. AOR?s MCHC is derived from New Zealand bovine bone: a pure extract sourced from pasture-fed, freerange livestock not subjected to routine antibiotics or recombinant bovine growth. hormone (rBGH). In accordance with the latest research, Pro Bones now also contains both MK-4 and MK-7 as sources of vitamin K2. A vegetarian glucosamine sulfate has also replaced the shellfish-sourced glucosamine HCl, making Pro Bones shellfish-free.