Calcium is the most abundant cation of the human body, averaging approximately 1 kg in a 70 kg man.
The human body requires more calcium than any other mineral. The adult human body contains about 1,000 to 1,200 mg of calcium, with at least 99 percent of the calcium found in bones and teeth, giving them strength and rigidity.
The 1% of the body’s calcium is distributed between the extracellular fluids and various soft tissues, perpetuating life by promoting normal muscle contraction, nerve transmission and a regular heartbeat.
Calcium is ingested in the form of relatively insoluble salts, whether the source is food or dietary supplements.
They are many ways to get enough calcium into the diet, including dairy products and dark green vegetables that are naturally rich in calcium. Other foods, such as cereals, juices, breads and tofu, can be fortified with calcium.
Because the mineral is absorbed only in the ionized form, it must first be released from these salts; therefore bioavailability of calcium from its various sources assumes much important in calcium nutriture.
The efficiency with which calcium is absorbed from a particular source is only one of the factors involved in the availability of the mineral to the body.
Getting enough calcium from food or supplements is essential because the human body doesn’t produce it.
If the body don’t get enough calcium in the diet, the body withdraws the mineral from bones to keep blood calcium concentration within a healthy range.
Removing calcium from bones for use in the rest of the body weakens existing bone. It also prevents the formation of new strong bone.
The human body absorbs calcium most efficiently in amounts of 500 mg or less.
A greater absorption does not necessarily mean greater retention. Sometimes increased absorption of calcium is offset by its increased excretion in the urine or digestive juice.
Calcium economy in the body is very complex, being influenced not only by exogenous factors but also by endogenous conditions.
Calcium in Human Body
