Extra iodine call - and more for mums

Pregnant and breastfeeding women will still need additional supplements to get sufficient iodine in their diet even after regulators compel bakers to use iodised salt.

These women should be advised to take iodine supplements to avoid babies developing goitre and mental retardation problems, says a report by a transtasman food regulator.

Food Standards Australia New Zealand (FSANZ) said it was referring the issue to health authorities and Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

It plans to require the salt used in baked cereal products - bread, breakfast foods and biscuits - to be iodised, but will cut the concentration of iodine in iodised salt from 25mg-65mg per kg to 20mg-45mg per kg so that young children don't get too much.

Though there is no formal policy for iodine supplements to be given to pregnant and breastfeeding women, FSANZ said adults required an average of 100 micrograms of iodine a day. A recent total diet survey showed females over 25 were only getting 40 per cent of the recommended daily intake.

Goitre problems - thyroid enlargement - are typically seen with an intake of less than 50 mcg of iodine a day and cretinism is seen in severe cases, in the babies of pregnant women who receive less than 30 mcg a day.

Medical experts say women having babies or breastfeeding should take up to 200 mcg of iodine supplements a day, unless they have thyroid disease or get a lot of iodine from sources such as seafood.

A lack of iodine during the development of a foetus usually means a baby will take iodine from the mother, whose own iodine levels drop further, with potential for a knock-on effect for her next baby to have an even lower reserve of iodine available.

The regulator said that in the short term, until the population is iodine-replete, supplementation for pregnant and breastfeeding women may be necessary.

Health Ministry official Dr Stewart Jessamine, the principal technical specialist at Medsafe, said dietary supplements were regulated by the Food Safety Authority, and it has said it is talking to the ministry about encouraging iodine for pregnant women.

Until now, the country has depended on the addition of iodine to table salt, but the trend of adding less salt to food and a change in the chemicals used to clean dairy vats and piping means people no longer inadvertently received a small amount of iodine in milk.

Iodine deficiency during pregnancy is the most common cause of preventable intellectual impairment. Children born to iodine-deficient mothers can grow up with a lower IQ, and learning, reading and hearing difficulties.

Elizabeth Aitken, senior adviser on nutrition at the Ministry of Health, said the suitability of recommendations for groups such as pregnant women and children would be assessed in compiling with the FSA a joint submission on the iodised salt proposal.


A question of balance

Plans to add iodine to the salt used in grain-based foods such as bread, biscuits and breakfast cereals should be balanced with advice about the risks of having too much iodine, says a Green Party spokeswoman.

"Mandatory fortification needs to be managed carefully to avoid overdosing," said Green MP Sue Kedgley.

"I am surprised that the proposal includes so many products - not just bread."

It was important that a considerable number of such products remained free of iodised salt for people who had an intolerance for iodine.

"It would be a severe imposition if they were restricted to a handful of products."

Iodine deficiency could lead to significant health problems, but "having too much iodine can also cause significant harm", she said.

- NZPA