Iodine deficiency
Iodine deficiency, most common in inland and mountainous areas, can predispose to goitre – if widespread, known as endemic goitre. Pregnant women deficient of iodine can give birth to infants with thyroid hormone deficiency. The use of iodised salt to add iodine to the diet has eliminated endemic cretinism in most developed countries, and over 120 countries have made the iodination of salt mandatory.