Calcium, in combination with phosphorus and other elements, is necessary to give strength to bonesFind out more about this term and teeth. When our dietary intake of calcium is greater than our bodies' requirements some of the excess calcium is stored in our bones. When our day-to-day intake of calcium does not meet requirements, the calcium stored in bone becomes available to meet this shortfall. Calcium has other important roles. It is essential for normal clotting of blood and is a vital link in transmission of nerve impulses. It is also an essential element in enzyme regulation, in the secretion of insulin in adults, and in regulation of muscle function.