Iodine is an essential micronutrient required daily in very minute quantities (100 – 150 micrograms) for normal human growth and mental development. The disorders caused due to deficiency of nutritional iodine in the food, diet are called Iodine Deficiency Disorders (IDD). The Goitre is only the tip of the iceberg. Iodine deficiency results in physical and mental retardation. It affects people of all ages irrespective of sex and socioeconomic status. It has also been reported that on an average, school children living in iodine deficient regions lose 13 IQ points compared to the school children living in iodine sufficient regions. The various disorders associated with iodine deficiency are given in Table 1.
It is estimated that more than 200 million people are at risk of IDD in India, while the number of persons suffering from goitre and other iodine deficiency disorders is above 70 million. The surveys conducted by the Central and State Health Directorates, Indian Council of Medical Research (ICMR) and Medical Institutes have clearly demonstrated that not even a singe State/Union territory is free from the problem of IDD. Samples surveys have been conducted in 28 states and 7 Union territories which have revealed that out of 324 districts surveyed so far, 263 districts are IDD endemic, i.e. the prevalence of IDD is above 10 per cent.
Supplementation of iodine through salt in the form of iodised salt in the diet has proved cost effective in controlling and eliminating IDD. Since salt is consumed by all everyday, the supply of iodised salt will ensure the availability of iodine for normal body function.