What is iodine?
Iodine is a trace mineral that your body uses in small amounts to synthesise thyroid hormones that are necessary for regulating your body’s growth, development, metabolism and body temperature. Most iodine in your body is found in the thyroid gland, but some is also found in the blood and muscles.
Where do we find it?
Good food sources of iodine include seafood, bread (all Australian bread is now made with iodised salt – organic and ‘no added salt’ breads are the exception), seaweed, dairy and eggs. Some vegetables have iodine, but only of grown in iodine rich soil. Iodised salt is obviously high in iodine, however eating too much salt can contribute to many other health issues. NB: Although it comes from the sea, sea salt is a poor source of iodine.
How much do we need?
The recommended daily intake of iodine we need is very small (around one teaspoonful over a lifetime for most adults) when compared to other nutrients and is measured in micrograms (mcg)
1 – 8 years old 90mcg
9 – 13 years old 120mcg
14+ years old 150mcg
(Pregnancy and breastfeeding 220mcg and 270mcg respectively)
What is iodine deficiency?
If you do not have enough iodine in your body, you cannot make enough thyroid hormone. Thus, iodine deficiency can lead to enlargement of the thyroid (goiter), hypothyroidism and to mental retardation in infants and children whose mothers were iodine deficient during pregnancy.
Low dietary levels of iodine were thought to be a problem in the past or in developing countries only. However, some researchers suspect that iodine intake levels in Australia have dropped considerably, perhaps by as much as half, over the past few decades. Ongoing research is underway to look at the problem and what might be done about it. Approximately 40% of the world’s population remains at risk for iodine deficiency.
Some reasons for low iodine intake may include:
- Consuming most of our salt in processed foods as manufactures do not used iodised salt in processed foods (and, until recently, in bread)
- Less iodine in milk because of changes in treatment methods
- A possible reduction of iodine levels in Australian soils
- A reduction in the use of salt in cooking and table salt (particularly iodised salt).