Spot urinary iodine concentration as a measure of dietary iodine, evaluated in over 3800 young male subjects undergoing medical check-up preliminary to military enrolment in Piemonte and Aosta Valley (Italy).

The aim of the study was to assess iodine status in over 3800 young male subjects aged 18, living in 6 different provinces of Piemonte and in Aosta Valley, Italy. A cross-sectional study on 3837 young male subjects undergoing medical evaluation preliminary to military enrolment was performed. Spot urine samples were obtained in the morning hours and urinary iodine was measured by a colorimetric method. As outcome measure iodine status, based on spot urinary iodine median concentration, categorised as sufficient (>99 microg/l), mild deficiency (50-99 microg/l), moderate deficiency (20-49 microg/l) and severe deficiency (<20 microg/l), was obtained. Median urinary iodine concentration was 101.8 microg/l in our sample. Moderate-to-severe iodine deficiency was found in <10% of all subjects. Mild iodine deficiency was found in <40% of the subjects, with greater variability within the provinces considered. For each geographical area significant differences can be observed in more than 50% of the comparisons of the confidence intervals related to the frequencies of samples with spot urinary iodine concentration below 100 microg/l. The high frequency of mild iodine deficiency found in our sample suggests that dietary sources of iodine in Piemonte, Italy, have improved since the last evaluation 25 yr ago (2) but may still be insufficient. Further population studies are required.