What Is the Role of Calcium in the Body?

Calcium is a vital nutrient and an insufficient amount of calcium in the body will cause adverse health effects. The skeleton, for instance, requires a steady supply of protein, calcium and other nutrients to stay strong and healthy so it can support the body, protect internal organs, and provide anchor points for muscles. This nutrient forms the bulk of skeletal structure; without an adequate intake of calcium, bones become weak and brittle. The role of calcium in the body is more complex than just providing strong bones and teeth, however. It is also responsible for nerve impulse transmission, blood clotting, and muscle cotnraction.

One function of calcium in the body is as an electrolyte for nerve impulse transmission. Without calcium providing free electrons, the neurochemical impulses that the nervous system uses would have no way to travel efficiently. Other electrolytes in the body include sodium, potassium, chlorine and magnesium. These elements are metals, which easily conduct electrical signals due to their abundance of free electrons in their valence shells. Calcium exists in plasma, the liquid solution in which cells are suspended, and inside cells, providing a balanced chemical transmission trail.

Blood clotting is another important role of calcium in the body. As soon as the skin is broken, blood interacts with the oxygen and nitrogen in the surrounding air and, along with vitamin K, begins pulling platelets together. Without adequate amounts of calcium, this reaction cannot occur, and the coagulation, or clotting, of blood will take longer. In extreme cases this could lead to a fatal hemorrhage, especially if a major blood vessel undergoes damage.

The other main function of calcium in the body is muscle contraction. A person's muscle tissue consists of individual fibers linked by neurons to the central nervous system. When a muscle receives the signal to contract, the calcium ions within the muscle electromagnetically attract the myosin, the actual muscle fiber, causing it to contract. As muscle tissue is elastic, it returns to its natural state almost instantly; therefore, a continuous influx of calcium is required to keep the muscle contracted or to contract it further.

The body cannot synthesize or produce calcium. Without a regular influx of calcium in the diet, the body will take it from bones and teeth, leading to bone weakness. Common sources of calcium are dairy products such as milk and cheese. Calcium supplements also exist, but they lack the nutritional value of dairy products, which also contain vitamin D.