Calcium and phosphorus and why the human body needs them

Calcium (Ca⁺⁺) is a soft, silvery-white metallic element, its atomic number is 20, relative atomic mass 40.08. It is one of the alkaline-earth metals. It is the fifth most abundant element (the third most abundant metal) in the Earth's crust. It is found mainly as its carbonate CaCO₃, which occurs in a fairly pure condition as chalk and limestone. Calcium is an essential component of bones, teeth, shells, milk, and leaves, and it is the most abundant element in human body, on average about 1.5% of total body weight. Bones and teeth contain about 99% of the body calcium. The other 1% of the body calcium is distributed in both intracellular and extracellular spaces. The best food sources of calcium include milk, cheese, ice cream, yogurt, tofu, salmon, sardines, clams, oysters, turnip greens, mustard greens, broccoli, kale, legumes, and dried fruits.

The primary functions of calcium in the body include:

1. To mineralize teeth mineral components.
2. To facilitates interaction between proteins or between proteins and phospholipids in cell membrane.
3. To participate blood clotting, nerve impulse transmission, muscle contraction, enzyme regulation, and membrane permeability.
4. To be the major structural element in bones and teeth. The mineral component of bone consists mainly of nerve impulse transmission, which contain large amounts of calcium and phosphate. Bone is a dynamic tissue that is remodeled throughout life.
5. To mediate the constriction and relaxation of blood vessels, and the secretion of hormones.

Phosphorus (P) is highly reactive, non-metallic element, its atomic number 15 and relative atomic mass 30.9738. It occurs in nature as phosphates, and is essential to plant and animal life. Phosphorus is the second most abundant element in human body. About 85% of the body's phosphorus is in the skeleton, and the remainder is associated with organic substances of soft tissues. Foods of animal origin such as meat, poultry, fish, eggs, milk, and milk products are superior sources of available phosphorus compared to cereals and soya-based foods.

Phosphorus is of paramount importance in the development of skeletal tissues which are the store of 85% of the total body phosphorus. In the bone, phosphorus exists as compound, calcium phosphate and the crystal, hydroxyapatite which are involved with the bone formation process. Other phosphorus is in intracellular and extracellular fluid. In cells, phosphorus is of vital importance in intermediary metabolism of the energy nutrients, contributing to the metabolic potential in the form of high -energy phosphate bonds, and through phosphorylation of substrates.

Phospharus is also an important component of the nucleic acids DNA and RNA, which are responsible for the storage and transmission of genetic information. Combined with lipids, phosphorus is an important structural component of cell membranes. Phosphorus also functions in maintaining acid-base balance by acting as one of the body's important buffers.

From the above discussion, it's very obvious why human body needs Ca⁺⁺ and P. If one of them or both is insufficient for normal molecular and biological processes taking place in our body, our health will be jeopardized. For example, insufficient blood Ca⁺⁺ leads to tetany, a symptom manifested by intermittent muscle contractions, muscle pain, muscle spasm. Deficient in calcium in adult can cause osteoporosis - loss of bone mass. Although P deficiency is rare, due to some special occasion, P deficiency may develop, which may lead to myopathy, weakness, and cardiomyopathy. Certainly, if anyone of them is in excess of body need, it is not good either, because all the nutrients in the body work together cooperatively to maintain normal body functions. Both calcium and phosphorus have to be in the right amount and proper relation to each other to maintain normal health.