Our bodies must have an adequate intake of iodine to form the hormones produced by the thyroid gland. These hormones regulate our bodies' metabolic rate. If the dietary level of iodine is inadequate, the gland, which is in the neck, swells and produces goitre. Unless treated, this condition can cause mental retardation and stunted growth in children, and hair loss, slowed reflexes, dry, coarse skin and other effects in adults. Foods produced in regions where soils are low in iodine, such as Tasmania in Australia, the Thames Valley in the U.K., and the north-west region of the U.S.A., are deficient in this element. Goitre caused by iodine deficiency can be prevented by supplementing the diet with added iodine. This is commonly done by adding sodium iodide to table salt to produce iodized salt. For some people, iodized salt can be an important source of iodine, and a change to a low-salt diet should make allowance for the decrease in iodine intake. Some foods, such as cabbage, sprouts and other brassicas contain natural anti-thyroid substances. In circumstances where both large quantities of these foods are eaten and the levels of dietary iodine are marginal, goitre could develop.

IODINE INTAKE

Excessive amounts of iodine can also lead to goitre. This has occurred where foods, such as seaweeds, which are rich in iodine, are commonly eaten. Although excessive iodine intake is not common, it should be noted that, in addition to food, many cough medicines and milk contaminated with an iodine containing sanitizing agent also contribute to iodine intake. But it is unlikely that any harmful effects would occur with habitual intakes up to 300 micrograms per day.

Recommended daily dietary intake of iodine (Australia):
Infants: Children: Adult men: Adult women: Pregnancy: Lactation:	50-60 micrograms 70-150 micrograms 150 micrograms 120 micrograms 150 micrograms 200 micrograms

IODINE RDI:

 

FIGURE 52: IODINE CONTENT OF SOME FOODS

FOOD	IODINE CONTENT   (micrograms per 100 grams of food)
Salt (iodized) Seafood Vegetables Meat Eggs Dairy products Bread and cereals Fruits	3000 66 32 26 26 13 10 4

	Elements
	-	Sodium
	-	Potassium
	-	Calcium
	-	Magnesium
	-	Iron
	-	Phosporus
	-	Sulphur
	-	Chlorine
	-	Copper
	-	Zinc
		Iodine
	-	Fluorine
	-	Chromium
	-	Manganese
	-	Selenium
	-	Cobalt
	-	Molybdenum
	-	Nickel
	-	Tin
	-	Silicon
	-	Vanadium
	-	Cadmium

Also on this page:

-  Iodine intake
-  Iodine RDI
-  Figure 52: Iodine
   content of some food