Last update: Nov. 2007

Sustainable elimination of iodine deficiency disorders by 2005

Iodine Deficiency Disorders can be prevented by a simple solution

There has been dramatic progress over the past decade in the global campaign to eliminate iodine deficiency, the world's leading cause of preventable mental retardation and impaired psychomotor development in young children. In its most extreme form, iodine deficiency causes cretinism. It also significantly raises the risks of stillbirth and miscarriage for pregnant women.

Most commonly and visibly associated with goiter (an enlarged thyroid gland), iodine deficiency takes its greatest toll in impaired mental growth and development, which contributes to poor school performance, reduced intellectual ability, and impaired work performance.

In 1990, about 1.6 billion people, or 30 per cent of the world's population, lived at risk of iodine deficiency disorder (IDD); some 750 million people suffered from goitre, mainly because of chronically low iodine intake. An estimated 43 million were affected by some degree of brain damage as a result of inadequate iodine intake before or during infancy and early childhood, largely because of living in mountainous or flood-plain regions where erosion sapped the local soil and crops, leaving too little iodine for healthy thyroid function.

Salt iodization has been adopted as the main strategy to eliminate IDD as a public health problem, and universal salt iodization by 2005 has been set as a global target. While other foodstuffs can be iodized, salt has the advantage of being widely consumed and inexpensive. It has routinely been iodized in some industrialized countries since the 1920s.

Consumption of iodized salt has soared in the developing world over the last decade. In the early 1990s only around 20 per cent of households consumed adequately iodized salt, but today more than two-thirds (69 per cent) of households do. About 84 million newborns are now being protected from learning disabilities caused by iodine deficiency disorders.

As of 2005, 34 developing countries had reached the USI target and 120 developing countries had salt iodization programmes, compared with 90 countries in 2000. Eighteen countries increased their proportion of household consumption of iodized salt by 20 percentage points or more and maintained a level of 70 per cent or higher.

Still, faster progress is needed

There are large disparities in adequately iodized salt consumption among regions of the developing world. The highest levels are found in Latin America and the Caribbean and East Asia and the Pacific, while the lowest levels are in CEE/CIS. In Sub-Saharan Africa almost two-thirds of households consume adequately iodized salt.

Unit: millions of newborns Source: UNICEF global database

Yet there are still 36 countries in which less than half of all households consume adequately iodized salt. Some 38 million newborns are born every year unprotected from iodine deficiency and its lifelong consequences. To achieve universal salt iodization, even faster progress is needed.

Source for figures: UNICEF global databases.