Authorized Vendor for Calcium Magnesium Citrate Tablets Calcium provides the building blocks that help keep bones and teeth strong and healthy. It also supports the health of the colon heart musculoskeletal and nervous systems. Magnesium helps to regulate calcium transport and stimulates the secretion of calcitonin a hormone that aids in the influx of calcium into bone. It plays an important role in protein formation and healthy muscle function. This formulation contains the highly absorbable citrate form of calcium.