Iodine Deficiency Disorders
The effects of iodine deficiency on the growth and development of a population that can be revented by correction of iodine deficiency, denoted by the term IDD, are evident at all stages, including particularly the fetus, the neonate, and in infancy, which are periods of rapid brain growth. The term goiter has been used for many years to describe the enlarged thyroid gland caused by iodine deficiency (Figure). Goiter is indeed the obvious and familiar feature of iodine deficiency, but knowledge of the effects of iodine deficiency on brain development has greatly expanded in the past 30 years
A hypothyroid cretin from Sinjiang, China, who is also deaf mute. This condition is completely preventable.
Correction of Iodine Deficiency
Iodized Salt
Since the successful introduction of iodized salt in Switzerland and the United States in the 1920s, successful programs have been reported from a number of countries, including those in Central and South America (e.g., Guatemala and Colombia) and Finland and Taiwan.
Universal salt iodization (USI) for India and subsequently for many other countries. This policy includes legislation to provide for compulsory iodization of all salt for human and animal consumption, and this legislation makes it illegal for noniodized salt to be available for human or animal consumption.
Potassium iodate is the preferred vehicle compared to potassium iodide because of its greater stability in the tropical environment. A dose of 20–40mg iodine as potassium iodate per kilo is recommended to cover losses to ensure an adequate household level. This assumes a salt intake of 10 g per day.
Iodized Oil
Iodized oil by injection or by mouth is singularly appropriate for isolated communities characteristic of mountainous endemic goiter areas. The striking regression of goiter following iodized oil administration, with improved well-being from correction of hypothyroidism, ensures general acceptance of the measure.
Iodized oil is more expensive than iodized salt but is used especially for severe iodine deficiency in remote areas. It provides instant correction of the deficiency and the consequent prevention of brain damage.
In a suitable area, the oil (1 ml contains 480 mg iodine) should be administered to all females up to the age of 40 years and all males up to the age of 20 years. A dose of 480 mg will provide coverage for 1 year by mouth and for 2 years by injection.
Iodized Milk
This is particularly important for infants receiving formula milk as an alternative to breast-feeding. An increase in levels from 5 to 10 mg/dl has been recommended for full-term infants and 20 mg/dl for premature infants. However, breast-fed infants will be iodine deficient if the mother is iodine deficient.
Iodized milk has been available in the United States, the United Kingdom and Northern Europe, Australia, and New Zealand as a result of the addition of iodophors as disinfectants by the dairy industry.
