Relationship between salt consumption and iodine intake in a pediatric population

PURPOSE: The World Health Organization recommends reduction of salt intake to < 5 g/day and the use of iodized salt to prevent iodine deficiency states. A high prevalence of excess salt consumption and an inadequate iodine intake has been previously shown in an Italian pediatric population. It was appropriate, therefore, to analyse in the same population the relationship occurring between salt consumption and iodine intake. METHODS: The study population was made of 1270 children and adolescents. Estimates of salt consumption and iodine intake were obtained by measuring 24 h urinary sodium and iodine excretion. RESULTS: The iodine intake increased gradually across quartiles of salt consumption independently of sex, age and body weight (p < 0.001). Median iodine intake met the European Food Safety Authority adequacy level only in teenagers in the highest quartile of salt consumption (salt intake > 10.2 g/day). We estimated that approximately 65–73% of the total iodine intake was derived from food and 27–35% from iodized salt and that iodized salt made actually only 20% of the total salt intake. CONCLUSION: In this pediatric population, in face of an elevated average salt consumption, the use of iodized salt was still insufficient to ensure an adequate iodine intake, in particular among teenagers. In the perspective of a progressive reduction of total salt intake, the health institutions should continue to support iodoprophylaxis, in the context of the national strategies for salt reduction. In order for these policies to be successful, in addition to educational campaigns, it is needed that the prescriptions contained in the current legislation on iodoprophylaxis are made compelling through specific enforcement measures for all the involved stakeholders. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00394-020-02407-w) contains supplementary material, which is available to authorized users.