Effect of iodine supplementation on goiter prevalence among the pediatric population in a severely iodine deficient area

We evaluated goiter status and urinary iodine excretion (UIC) of 304 school-children (7-12 years old) 3 years after a law was passed for mandatory production of iodinated salt in an area previously characterized by severe iodine deficiency in Zonguldak, a mountainous city in the West Black Sea region in Turkey. We examined all the children for goiter by palpation, measured sonographic thyroid volumes (STV) and UIC. Eighty-two percent of families had been using iodinated salt. UIC was above 100 microg/l in 71.2% of the children and median UIC was sufficient (143.5 microg/l). The prevalence of goiter was lower at ultrasound (14.6%) than by palpation (19.4%). Median STV values were within recommended normal limits at all ages. Although Zonguldak had been a highly endemic region, it became mildly endemic 3 years after mandatory iodination of salt, with decrease of goiter prevalence.