Is The Iodation Of Salt Essential?
Iodine deficiency in humans can be traced to the depletion of iodine from the soil.
Most of the world's iodine is found in oceans, although it is also present in soil. Over the centuries, large amounts of iodine have been leached from surface soil by rain and carried back to sea. Iodine then returns to the soil via rainfall after being absorbed into the atmosphere from the sea's surface. But the return is slow and small, compared with the original loss.
Repeated flooding of areas also increases the depletion of iodine from the earth. All crops grown in these areas therefore lack iodine, and as a result, people who are dependent on food grown in that soil become iodine deficient.
Why We Need Iodine
In the human body, iodine is part of the thyroid hormones, which are essential for normal physical and mental development. A lack of iodine in the diet results in a number of Iodine Deficient Disorders (IDDs) in people of all ages. IDDs include goitre (enlargement of the thyroid gland); still-births; loss of energy; reduced mental ability; and retarded physical development.
It is estimated that 1.6 billion people throughout the world are living in iodine-deficient environments. About 200 million are suffering from goitre, while 20 million have preventable brain damage. In South Africa there are areas where the population exhibits IDDs, with increasing evidence that this problem is greater than previously thought.
The various effects of IDDs result in human suffering, increased medical expenses, poor educational results and fewer job opportunities. The elimination of IDDs could therefore have tremendously positive results.
Early Stages Of IDDs Can Be Cured
When goitres and brain damage have been caused by lack of iodine, they can be cured in the early stages by large doses of iodine, but in later stages, there is no help for the sufferers.
Extra iodine can be provided in several ways. Fortification of salt is the most common way of supplying iodine in the daily diet. Potassium iodate is used; the cost is low, the process is simple, iodine intolerance is very rare and the benefits are enormous. It is important to note that iodine does not affect the colour or taste of the salt. There is no difference between iodised and iodated salt - iodated simply refers to the fact that potassium iodate is used.
Through encouragement from UNICEF (United Nations Children's Fund) and agreement by heads of state of many countries; there was a worldwide objective to eliminate IDDs as a public health problem by the end of the twentieth century through the compulsory addition of iodine to salt.
In South Africa the National Department of Health passed a regulation that after 1 December 1995, all salt sold in stores must be iodated at a concentration of 40-60mg/kilogram (40-60 parts per million) at the time of packing.
Normal daily consumption of salt will supply all the iodine an adult needs, although a much higher consumption than this is still perfectly safe.
Non-iodated salt remains available in pharmacies for the few people who are iodine intolerant. Salt sold to food manufacturers is also iodine-free.
"Iodine deficiency is so easy to prevent that it is a crime to let a single child be born mentally handicapped for that reason." Henri Labouisse, Executive Director, UNICEF, 1978.
F.A.C.S. Scientific Director. 1995. (Update 2017 imminent)