Written by Sharyn Morgan

Iodine is needed to produce thyroid hormones that are vital for the growth & well-being of many organs in the body, particularly the brain. And that lack of iodine in the diet has historically led to hypothyroidism, a condition that can have serious health consequences, not just for the thyroid but for other parts of the body as well.

A history of iodine supplementation

Given the low levels of iodine in our food supply these days, it is recommended that supplementary iodine be consumed, particularly by pregnant women to ensure the normal development of the brain of the developing baby.

Dr Bott says that the lack of iodine in the Australian diet became so significant a health issue that in the 1950s a public health campaign pushed for the addition of iodine to salt and bread. In 1968, Tasmania established a thyroid advisory committee to address the problem.

Since the 1950s a lot has changed, not always for the better. Milk producers used to clean their vats with iodine, making milk an important source of the mineral, but that changed when they replaced iodine in favour of chlorine as the cleaning agent.

Research in Tasmania in the 1990s again showed deficiency in children and the state government negotiated with bakers to add iodised salt in all bread made in the state from 2001. In 2009 this action was put into legislation nationally. However, with the uptake of low carbohydrate diets, getting sufficient amounts of iodine is still an issue with advocates calling for it to be added to other foodstuffs.