Calcium is the most important mineral in the body. The body needs calcium for normal functioning of nerves and muscles including the most important muscles of all which is the heart. Calcium is also important for healthy bones and teeth. The amount of calcium in the blood is carefully controlled by the body’s hormonal systems. The body gets calcium from diary products, some vegetables (such as broccoli), and some fortified foods. Calcium can also be obtained from taken pills containing calcium. Most of the body’s calcium is stored in the bones and only small amount is found in the blood (serum). Calcium is maintained within a fairly narrow range from 8.5 to 10.5mg/dl (4.3 to 5.3meq/l or 2.2 to 2.7mmol/l). The estimation of serum calcium level is fraught with possible errors. Several means of contamination might lead to false elevations of serum calcium concentration. Before the test is carried out, one does not need to fast or limit ones activity before the test. Rather certain medicine/drugs needed to be avoided before the test, because they might affect the test result. The result of the experiment can be calculated, since the differences in serum calcium is significance with the age differences. Those with the age bracket (50 years & above) have lesser serum calcium level than those in the range of 20 to 30 years.