Iodine in bread not enough for pregnant women

Research from the University of Adelaide shows that iodized salt used in bread is not enough to provide healthy levels of iodine for pregnant women and their unborn children.

The study - led by researchers from the University's Robinson Institute – has prompted calls for pregnant women to keep taking iodine supplements.

Iodine deficiency is recognized by the World Health Organization (WHO) as the most common preventable cause of brain damage in the world.

"Iodine is an essential element which is important for human brain development and thyroid function," says one of the lead authors of the study, Associate Professor Vicki Clifton from the University's Robinson Institute and the Lyell McEwin Hospital.

"In 2009, Australian bread producers began a mandatory program of iodine supplementation in bread to help provide a boost to iodine levels in the community. Our study was aimed at determining whether or not that was having a positive impact on iodine levels for pregnant women."

In the study, almost 200 South Australian women were tested throughout their pregnancy and six months after giving birth.

"We found that South Australian women are mildly iodine deficient. Despite the inclusion of iodized salt in bread, women who were not taking an iodine supplement during pregnancy were still suffering from iodine deficiency," Associate Professor Clifton says.

"Those women who were taking a supplement in addition to eating bread with iodized salt were receiving healthy levels of iodine, well within WHO guidelines."

This is the latest study to follow on from the pioneering work of the University's Emeritus Professor Basil Hetzel AC, who began researching iodine deficiency more than 50 years ago at the Queen Elizabeth Hospital, in collaboration with the Papua New Guinea Public Health Department.

Why iodised salt is necessary

Iodine helps prevent brain damage and mental impairment and is especially important for brain development in unborn babies. The wet New Zealand climate means iodine is not available in sufficient quantities in the plants and animals we eat. Fortifying bread with iodine:

helps increase the amount of iodine in New Zealanders’ diet
prevents iodine deficiency from becoming more serious in future.

Products that require iodised salt

You must use iodised salt in almost all bread and bread products. The standard defines the bread and bread products that must contain iodised salt.

Exceptions

There are some exceptions to the use of iodised salt, including: