Minerals have numerous functions in the human body. Sodium, potassium and chlorine are present as salts in body fluids, where they have the physiological function of maintaining osmotic pressure.
Minerals are part of the structure of many tissues. For example, calcium and phosphorus in bones combine to give firm support to the whole body. Minerals are found in body acids and alkalis; For example, chlorine is in the hydrochloric acid in the stomach. They are also essential constituents of certain hormones, for example the iodine in the thyroxine produced by the thyroid gland.
The main minerals in the human body are: calcium, phosphorus, potassium, sodium, chlorine, sulfur, magnesium, manganese, iron, iodine, fluorine, zinc, cobalt and selenium. Phosphorus is found so widely in plants that a lack of this element may not be present in any diet.
Potassium, sodium and chlorine are easily absorbed and physiologically they are more important than phosphorus. Humans consume sulfur mostly in the form of sulfur-containing amino acids; therefore, when there is lack of sulfur, it is related to lack of protein.
The lack of copper, manganese and magnesium is not considered common. The most important minerals in human nutrition are: calcium, iron, iodine, fluorine and zinc, and only these are discussed in detail here.
Some mineral elements are needed in very small amounts in human diets but are vital for metabolic purposes; they are called “essential trace elements”.