There is more calcium in the body than any other minerals calcium and phosphorus account for 75% total mineral elements in the body.
Calcium is necessary for building of bones and teeth, for normal clotting of blood and functioning of the muscles. It helps in the contraction of the heart muscle While potassium favors its relaxation; calcium together with other mineral elements gives rigidity and permanence to bones end teeth.
Calcium helps in regulating the permeability of cell membrances conduction in the nervous system and the beating of the heart. The level of serum calcium is maintained by excretion of calcium from the bone. Calcium also forms a component of some important enzymes.
Milk and milk products are excellent sources of calcium in the daily diet. Among the cereals, ragi is rich in calcium. Green leafy vegetables such as, amaranth, drumstick leaves, methi, mint, spinach, carrot leaves are rich sources of calcium. Among animal sources- egg yolk, bones of animals and fish are good sources of calcium.
The daily requirement of calcium is about 1 to 1.5 grams for children, 0.7 to 1 gram for adult and 1.5 to 2 grams for pregnant or lactating women.
Deficiency of calcium results in retarded calcification of bones, enlargement of ankles and wrists and the person suffers from a disease known as rickets in children and osteomalacia in adults.