Iodine deficiency in childhood despite prevention. Current data from the Vienna area

: Since 1963 iodized table salt prophylaxis (10 mg KI/kg table salt) in Austria has led to a decrease in endemic goitre in children. Nevertheless, goitre frequency is rising again after the first two decades of life and iodine deficiency is found in 50% of the patients. In order to evaluate the adequacy of the iodine supply in childhood in the Vienna area the urinary iodine excretion was determined in 124 healthy non-goiterous children from 4 weeks to 16 years of age. Our investigation demonstrates a decrease in urinary iodine excretion in the older children (iodine excretion 400 micrograms/per g creatinine in the first year of life versus 96 micrograms I/per g creatinine after the age of 10, p less than 0.001). At the same time the number of children showing grade I iodine deficiency (according to WHO criteria) increases with age, so that more than 50% of children older than 10 years in the Vienna area have an insufficient iodine supply (p less than 0.0001). Thus, the iodine supply should be improved by increasing the level of iodization of table salt to 20 mg KI/kg and by the more frequent intake of food naturally containing a higher iodine concentration.