Calcium is the most abundant mineral in the body: the body of an adult contains more than one kilogram. Mainly contained in the bones and teeth, associated with vitamin D, it ensures their solidity. In children, it participates in bone growth. In seniors it helps prevent osteoporosis and bone fragility. Dairy products and some fruits and vegetables are rich in calcium. Deficiency (common in the elderly) can be counterbalanced by dietary supplement intake.