Human Requirements for Minerals and Trace Elements

Of the 4.5 kg of mineral ash in the body of man about 4 kg is in the skeleton. The major mineral elements are calcium, phosphorus, sulphur, potassium, sodium, chlorine, and magnesium. The trace mineral elements are: iron, copper, molybdenum, cobalt, zinc, manganese, chromium and possibly tin; iodine and selenium amongst the non-metals, possibly also fluorine as it assists in the prevention of dental caries (Tables I and II) Several other elements have been considered as possibly essential, namely, nickel, bromine, arsenic, vanadium, cadmium, barium and strontium. It is becoming of increasing interest to find that the abundances of the less common elements in human blood and in the earth's crust show a remarkably close correlation.