Microcrystalline Hydroxyapatite (MCHA) is a natural compound that makes up the crystalline matrix of bone and teeth, and is the substance that gives them their rigidity.* MCHA consists of highly absorbable calcium and phosphorus, which are the major mineral components of bone.* Bone Support Formula is a comprehensive bone support product that includes Magnesium and trace minerals, as well as Vitamins C, D and K2 to aid in the synthesis and maintenance of healthy bone tissue.*