Increase in Incidence of Hyperthyroidism Predominantly Occurs in Young People after Iodine Fortification of Salt in Denmark

Even a cautious iodization of salt results in an increase in the incidence rate of hyperthyroidism. Contrary to current concepts, many of the new cases were observed in young subjects, and are presumably of autoimmune origin. Furthermore, monitoring is expected to show a decrease in the number of elderly subjects suffering from nodular hyperthyroidism.