Review of Iodine and Salt Sources for Establishing Iodization Standards.

Objectives: The ICCIDD/GN Iodine Task Force was established in response to changing environment and program maturity of salt iodization programs worldwide. It aims to improve the evidence and thus the quality and effectiveness of iodine nutrition programs to help update program guidelines. To review dietary sources of iodine intake, including salt from different sources and other natural iodine sources to inform the development of iodization standards. Methods: A review of published literature and reports, data and/or information from national programs for eliminating iodine deficiency disorders was conducted to gather both knowledge and program experience. Results: Globally salt intake through processed foods is increasing; however, in many countries such salt is not iodized. Except for marine food, most natural food sources are low in iodine. In Western countries without mandatory Universal salt iodization, the most significant food groups contributing to iodine intake are dairy and cereal products, however, there is a large disparity in iodine content within and between foods due to natural variations. Little information exists regarding the additional dietary iodine via iodized livestock salt. Generally, iodine content in drinking water is low and contributes relatively little towards iodine intake of large populations. Conclusions: Natural sources of iodine in the diet as well as the iodine contribution via livestock salt as less informative for establishing national standards however, a key consideration is the source of dietary salt. Since most of the salt intake proceeds from industrial salt, iodine standards should be applicable to the total dietary salt supply.

Complementary Interventions for Preventing and Controlling Iodine Deficiencies in Pregnant Women, Infants, and Young Children.

Objectives: Inadequate dietary iodine is the main cause of preventable brain damage, posing a serious threat to intellectual development and productivity throughout the world. Salt iodization is the primary strategy for preventing and eliminating iodine deficiencies, and 76% of households worldwide have access to adequately iodized salt. In several settings, new interventions provide iodine containing products for vulnerable groups - pregnant and lactating women, infants (0-5 months), and young children (6-23 months). However, the extent to which these ‘complementary interventions' meet the iodine requirements of these groups has not been investigated. We therefore examined these interventions to understand whether they meet vulnerable groups' needs. We also estimated the number of recipients reached. Methods: We reviewed literature, household surveys, and guidelines to assess whether salt iodization can meet vulnerable groups' iodine requirements. Then, complementary interventions used in public health contexts were mapped, their iodine contribution estimated, and the number of recipients reached calculated. Results: Our analysis suggests that salt iodization may meet the requirements of pregnant and lactating women, but possibly not all infants and young children. There is great variability in objectives, delivery methods, and iodine contribution of complementary interventions. The coverage of various complementary interventions ranges from 0 to 13% of the vulnerable population groups. Conclusions: There is a need for careful coordination to ensure appropriate amounts of iodine are delivered to recipients. Failing to do so can result in the delivery of too little or too much iodine, which can have negative health consequences.

Improving the Accuracy of Iodization of the Dietary Salt Supplies of Populations.

Objectives: The mandate of this working group was to assess the importance of salt iodine quality in successful IDD prevention and control. Examine the role of salt iodine content in quality assurance, inspection, surveillance, and coalition oversight of IDD programs. Methods: Scientific literature, technical reports and a range of data and information sources were reviewed to determine whether accurate salt iodization was making a critical contribution toward safe and successful IDD programs. Results: Evidence and examples were collected on salt iodine data in quality assurance of iodization by salt industry, assessments of iodized salt quality by inspectors in factories and markets, surveillance of USI strategies and dietary iodine supplies by program managers, and in provision of coalition oversight by high-level officials. Conclusions: Because salt iodization is a supply-based strategy, reliable accuracy at the source is most critical. It is therefore vital that each salt factory should adopt a quality management system, with standard operating procedures at least for the manufacturing and packaging of iodized salt. Titration is preferred but other quantitative methods with e.g. the WYD Checker, i- Reader or Bioanalyt can also yield accurate data. Improved accuracy down the supply chain is desirable, especially in surveillance, but commonly points to the need for ensured accuracy at the source when quality failures are discovered. The need remains for an agreed approach to obtain reliable data of the use of iodized salt in the food manufacturing industry.