Iodized Salt

Iodine is an essential nutrient needed by the body for the production of hormones. These hormones are manufactured by the thyroid gland and are therefore commonly known as thyroid hormones. Thyroid hormones have many functions in the body, all of which are essential for normal physical and mental development, including growth. Insufficient iodine intake can have serious consequences on long term health.

It is essential that pregnant women consume enough iodine in their diet since the brain is particularly sensitive to iodine deficiency during its formation. Iodine deficiency diseases (IDD) in pregnant women can result in abortion, stillbirth, congenital anomalies, mental retardation and growth retardation. At its most severe, IDD can result in significant mental retardation but more commonly, and less well known, is the fact that many children suffering from iodine deficiency have a reduction in learning capacity and the reason is often not discovered. Typically they can have IQs that are 10–15 points lower than those of other children.

Iodine is not just important for pregnant women however, if a diet contains insufficient iodine, the thyroid gland cannot make enough thyroid hormone to satisfy the body’s need. The thyroid gland becomes enlarged due to its desperate efforts to produce the hormone; this enlargement is known as goitre.

Iodine deficiency is a surprisingly unreported condition despite the fact that the World Health Organisation (WHO) estimates that 655 million people worldwide are suffering from goitre and 50 million are affected by a degree of IDD related brain damage. There is also a mistaken belief that only the population of developing countries are at risk from IDD but research has shown that iodine deficiency is most common in European countries where there is still a lack of consumer awareness of the dangers.

Iodine is only present in certain foods, such as fish and seafood and these are not always consumed regularly by everyone. For this reason, in 1990 the UN World Summit for Children in New York called for the elimination of ID disorders and in 1992, set the objective of Universal Salt Iodization (USI) – i.e. iodine to be added to all salt intended for consumption. The reason salt was deemed to be the most suitable vehicle for iodine was because salt is the most commonly available food item, which everyone everywhere consumes daily and because the process of adding iodine to salt is straightforward and cheap. For further information please see our position paper on Iodized salt.

Depending on whether iodized salt is manufactured in a continuous or batch process, a plant-specific testing plan must be drawn up for the implementation of quality monitoring. Three well-established testing methods which have been validated in interlab studies are available to determine the iodine content in food grade salt: