Iron plays an important part in the metabolic processes of the animals, being a vital representative in the cells of all mammals. The function of the iron in the body is limited almost exclusively to the oxygen transport in the blood, through the hemoglobin. It is also present in some enzymes that catalyze reactions of cellular oxidation. In the human body, the richest organs in iron are the liver and the spleen. Although in smaller amount, it is also present in the bones, in the medulla, in the kidneys and in the intestines.

An adult man absorbs about 5 mg of iron a day, while the woman absorbs slightly more to compensate the losses during menstruation or pregnancy. The absorption of iron is larger in children, exceeding 10 to 15 mg a day. There are several ferrous salts, as the ferrous sulfate, that are quite effective in the anemia treatment due to the deficiency of iron.

Of the richest victuals in iron stands out the liver, the fish and the egg yolk. The beans and the peas and, in a general way, all the green vegetables are richer in this element.