Optimizing iodine nutrition in Belgium: a selective, progressive and monitored approach to control iodine deficiency

Since 1990, many countries world-wide implemented salt iodisation programs in an effort totackle iodine deficiency. It was however only during the last few years that an effort wasundertaken in order to eliminate iodine deficiency as a public health problem in Belgium. In autumn 1998, a nation-wide study among children clearly showed mild iodine deficiency inBelgium, but no action was taken before 2009. It was only in the framework of the firstNational Nutrition and Health Plan 2005-2010 that iodine deficiency was formally recognizedas a public health problem. An agreement between the Ministry of Health and the bakerysector in April 2009 aimed to encourage and increase the use of iodised salt in theproduction of bread. A selective and progressive approach was used in order to keep controland to avoid a too rapid increase of iodine intake or an excessive iodine intake among thepopulation. It was calculated that the net yearly savings after installation of such a programamount to at least 14 million Euros a year.A recent national survey among school-aged children in autumn 2010 showed a clear andsignificant improvement in iodine status compared to more than 10 years ago, suggestingiodine sufficiency among school-aged children. The median urinary iodine concentration washowever at the lower end of the optimal range and seasonal effects were not taken intoaccount. The improvement was at least partly linked to the increasing use of iodised salt inthe bakery industry. However, some further silent iodine prophylaxis might also haveoccurred, due to changing dietary habits (milk and fish consumption). Pregnant women andwomen of child-bearing age in Belgium were found to still suffer from mild iodine deficiencyaccording to the current recommendations. This is at least partly linked to their lowerconsumption of milk and dairy drinks compared to children and due to the higher iodinerequirements during pregnancy. Although the use of iodine-containing supplements amongpregnant women was found to be quite high in Belgium compared to other Europeancountries, because of the low iodine status among women of child-bearing age, womenbecame pregnant with a suboptimal iodine status.In view of these findings, a further increase in the use of iodised instead of non-iodisedhousehold salt and iodised salt by the bakers is recommended. In addition, one should putefforts in increasing awareness among the public and among health professionals withregard to iodine-rich food sources and with regard to the use of iodine-containingsupplements starting before conception and continuing during lactation.In order to further improve iodine status in Belgium and sustain an optimal iodine statusover time, a legal framework is necessary. Mandatory fortification of all household salt andbread is recommended, while non-iodised alternatives could still be offered upon specificrequest. A rigorous monitoring program is indispensable, including vulnerable groups such aspregnant and lactating women and infants. In addition, sustainability is a key issue as iodinedeficiency re-emerged in several industrial countries due to lack of interest, regulations andmonitoring. Political willing, salt reduction measures, changes in dietary habits among thepopulation and changes in industrial practices all may affect iodine status in Belgium in thefuture. Therefore the strategy of controlling iodine deficiency needs to be directed andmonitored by a Belgian Scientific Committee for the Control of iodine deficiency disorders.Doctorat en Sciences biomédicales et pharmaceutiques