Minerals may be defined as those elements which remain largely as ash when plant and animal tissues are burnt. The human body contains more than 19 minerals, all of which must be derived from foods. A total of 4% of the body weight is made up of minerals. Some of the important minerals found in our body include calcium, phosphorus, iron, iodine, sodium, potassium, zinc and chloride.
All these minerals are derived from the food we eat. Of these, calcium, phosphorus, sodium, potassium, chloride and magnesium are the minerals required in larger amount by the body. Calcium and phosphorus, accounts for three-fourth of the minerals present in the body, and five other elements account for most of the rest. Many of these elements are present in such minute amounts that they are referred to as a trace elements or micronutrients.
Minerals are important for the body in various ways. They are required to form such organic compounds like phosphoproteins, haemoglobin and thyroxin. Hard skeletal structures are formed with the help of elements like calcium, phosphorus and magnesium, whereas soft tissues contain a relatively high proportion of potassium. Mineral elements are also required in the constitution of enzymes, for maintaining osmotic pressure and water balance between intracellular and extracellular compartment, for proper functioning of the nervous system, for muscular contraction and so on.