Iodine is a mineral.

 A lack of iodine in a child's diet can affect brain development or cause Goitre (where a part of the body called the thyroid gland becomes larger), hearing and speaking difficulty, & poor growth.  It remains the largest cause of mental retardation in the world today.  If a pregnant woman is highly iodine deficient (lacking in iodine) it may cause her to have a miscarriage or give birth to a still born baby.

A common method used to combat a lack of iodine is to add iodine to salt at the point of manufacturing.  This happened first in developed countries, however, by 2000 nearly 2/3 of developing countries iodised their salt.  The problem still remains huge.  In India the people most at risk are the poorest 300 million people as they are more likely to buy non-iodised salt as the poorer grades of salt, which are not iodised, are cheaper.

It is easier for some countries to iodise salt than others.  For example if all salt comes from only a couple of sources it is not a big thing to co-ordinate, however, if there are multiple producers of salt it gets complicated.  In Pakistan there are 600 small salt producers in remote areas who use old methods to produce their salt – now this makes it a challenge!!

Once a country has a reasonable level of salt iodisation the challenge is to maintain the level to keep the condition of iodine deficiency from re-emerging.  Producers of salt need constant encouragement and the public need to be continually educated about the benefits of using iodised salt in their cooking. In June of 2005 India re-introduced a ban on non-iodised salt as salt iodisation had been dropping over the last few years.  In some developed countries mild iodine deficiency is beginning to show again.

Iodine deficiency (a lack of iodine in the body) used to be a common problem in New Zealand as we do not have a lot of iodine in our soil and, therefore, in our food.  We first began putting iodine into our salt supplies in 1924 and in 1938 the amount we put in was increased.  In recent years different survey's have indicated the possibility of iodine deficiency re-appearing.  The "2002 National Children's Survey" published by the Ministry of Health showed mild iodine deficiency was showing in the population of children surveyed.

The reasons thought to contribute to the increase in low iodine levels in New Zealanders' include non-iodised salt being used in pre-prepared foods – which people are eating more of, Chefs and recipe books using non-iodised salt (such as sea salt), and subsequently people who cook at home not using iodised salt in cooking as reported by the New Zealand Medical Association.  As the symptoms of iodine deficiency are rarely seen and it has not been pushed by public health promotions over the last decade it is not surprising less people are aware of the need to have enough iodine.  Although it is still not a big problem New Zealanders' will need to be careful to make sure they get enough iodine in their diet.