Physical Function
Structural component of bones and teeth; role in intracellular and hormonal secretion regulation, muscle contraction, and activation of some enzyme systems.Calcium is maintained relatively high concentration in the blood and extracellular fluids, where it is needed to facilitate such functions as blood coagulation and intercellular communications.
The calcium in bones serves as a reservoir for calcium that is needed throughout the body. Bones and teeth contain more than 99 percent of the body’s calcium.
Calcium also is the key factor in normal transmission of nerve impulses. The movement of calcium into nerve cells triggers the release of neurotransmitter at the junction between nerves.
Calcium is a key component of the cell membrane and controls cell permeability and electrical properties.
Deficiency symptoms
A low calcium intake during the growing years limits the bones’ ability to reach their optimal mass and density.
The symptoms of calcium deficiency includes rickets, osteomalacia, osteoporosis, scurvy, tetany, parathyroid hyperplasia, stunted growth, laryngospasm.
Deficiency of calcium in young girls causes late puberty, irregular menstruation, excessive bleeding with crampy pain during this period, anemia and lowered state of body resistance against infection.
Food sources
Food sources of calcium include milk, milk products, sardines, clams, oysters, turnip greens, broccoli, legumes and dried fruits.Calcium is classically associated with dairy products: milk, yoghurt and cheeses are rich sources of calcium, providing the major share of calcium from foods in the general diet in the United States and Canada.
When substantial amounts of grains are consumed, for like breads or as maize, these can be important sources, although the calcium in cereals tends to be less bioavailable than that in dairy products.
Calcium
