Background — Both inadequate and high intakes of iodine are associated with thyroid disease and associated abnormalities. Consumption of foods deficient in iodine induces hypothyroidism. Conversely, excessive intake of the nutrient precipitates hyperthyroidism. Iodine deficiency causes impairment of thyroid hormonogenesis resulting in goiter (struma), cretinism which is associated with increased prenatal and infant mortality, deafness, motor disabilities and mental retardation due to damage during fetal and neonatal brain development.
We have assessed the iodine status of school children from the locality of Port Sudan, Red Sea State of Eastern Sudan. The primary sources of iodine of the children are mainly iodized salt and rations supplied by local donors and various aid agencies operating in the Sudan.
Methods — Male and female children (n=141), aged 6 to 12 years (median age 9.8 years), were selected for the survey using a multistage random sampling technique, between May 22 and August 25, 2006. All the children were assessed for urinary iodine and visible goiter. In addition, the iodine content of twenty salt samples was determined using the Iodometric titration method and spot test kits. The components of other foods that are routinely consumed by the children and households were noted using a questionnaire form.
Findings — Urinary iodine concentration exceeded 300µg/l and 1000µg/l in 65% and 9.9% of the children, respectively. The highest urinary iodine level was 1470µg/l. The prevalence of visible goiter was 17%. All the salt samples collected from the schools had more than 150mg potassium iodate per kg of salt.
Conclusions — The results of this pilot survey reveal that excessive intake of iodine in children exists in Port Sudan. Inappropriate and unregulated local fortification of salt and lack of monitoring of the imported and donated salt is the primary reason for the excessive intake. There is an urgent need for a regulatory mechanism during the process of iodine fortification and at the point of entry of imported and donated iodized salt as well as the mode of delivery in order to avoid hyperthyroidism and associated disorders. In addition, independent professionals should critically evaluate the health impact of excessive consumption of the nutrient.
