Iron “overload” in the South African Bantu

Summary Among the South African Bantu, the intake of iron is often very high—as much as 200 mg. per diem. This high intake is due mainly to the uptake of the element from iron utensils occuring during the preparation of their usual foods (particularly fermented cereal products). Published experimental evidence suggests that this level of iron intake is sufficiently high to overcome the “mucosal block” or the regulatory mechanism operating at everyday levels of intake, and allow unrequired iron to be absorbed, deposited and accumulated in the organs and tissues of the body. Observations by several workers show that excessive deposition of iron does, in fact, occur frequently; and that the incidence, age and sex affected, the morbid anatomical distribution of the element, and other characteristics, are all such as might be predicted to arise from oral iron overload. Although several conditions can cause or be accompanied by abnormal iron deposition—discussion suggests that intravenous iron, excessive destruction of erythrocytes, idiopathic haemochromatosis, and malnutrition, play little part in the siderosis observed in the Bantu. It is submitted that the abnormal deposition of iron in these people is due primarily to their habitually high iron intake. No lesion of the digestive tract or any other organ need be invoked to account for it. Furthermore, there appears to be no evidence that iron overload per se is detrimental to well-being.