Minerals play two important roles in the body :
I. as structural constituents of the body
II. as constituents of body fluids.
I. As structural constituents of the body they regulate several physiological processes:
(i) As constituents of soft tissues, such as tissue protein, cell bodies and muscles, they are responsible for their proper functioning.
(ii) They are found in compounds essential for the functioning of the body, e.g., iodine in thyroxin, zinc in insulin, Cobalt in Vitamin B12, sulphur in thiamine and iron in hemoglobin.
II. As constituents of body fluids, minerals have regulatory functions as:
(i) They contribute to the osmotic pressure of body fluids. Sodium salts and potassium salts are present in the intracellular fluids that influence their osmotic pressure.
(ii) They contribute to the maintenance of neutrality in blood and body tissues, by preventing the accumulation of too much acid or alkali. The chief base forming elements are sodium, potassium, calcium and magnesium. The acid forming elements are chlorine, phosphorus and sulphur.
(iii) Calcium, Potassium and Sodium maintain the normal rhythm in- heart beat.
(iv) They help nerves in maintaining a normal response to stimuli-especially by Calcium.
(v) They are essential for clotting of blood. Calcium is responsible for clot formation.