Bone-Up is a comprehensive formula that provides StimuCal MicroCrystalline HydroxyApatite (Mcha) from free-range New Zealand calves and micronutrients to support bone health. StimuCal is a naturally derived source of calcium shown to support bone mineral density better than calcium carbonate. StimuCal also provides bone proteins, including type I collagen. Vitamins D and K2 work together to support calcium deposition into bones.