Physiopathology of Iodine Nutrition

Iodine is an essential trace element whose only confirmed function concerns the formation of thyroid hormones. Our knowledge of the disorders caused by deficiencies in the dietary supply of many trace elements has markedly increased only during the last decade. Iodine is one exception to this rule. The role played by iodine deficiency in the etiology of disorders of the thyroid gland and in particular of endemic goiter has been documented for almost two centuries (1). Yet endemic goiter affects at least 300 million human beings in the world and still constitutes one of the major public health problems in the field of nutrition (2). This chapter reviews disorders resulting from iodine deficiency. It is shown that these disorders are found today not only in developing countries but also in industrialized countries in Europe, particularly in young infants.