New Zealand iodised salt policy has improved deficiency problem, report

Mandatory use of iodised salt in bakery across New Zealand has improved iodine deficiency levels in children, according to a ministry report.

In 2009 mandatory iodine fortification in bread was introduced across New Zealand and Australia and bakers have since been using iodised salt in all breads except organic and unleavened across both countries. This policy aimed to improve mild to moderate iodine deficiency levels identified in the New Zealand population.

A study conducted by New Zealand’s Ministry of Agriculture and Forestry (MAF) has found that children’s intake of iodine has ‘significantly improved’ since the mandatory bread fortification policy.

Jenny Reid, MAF food science and risk assessment manager, said there has been a “tremendous improvement”.

“The percentage of children estimated to have inadequate iodine intakes has dropped from 30% to 4% because of iodine fortification,” Reid said.

“The survey results indicate that we are achieving our goal of ensuring that more than 70% of school-aged children reach the ideal iodine intakes,” she added.

The findings also showed that only 1% of children are consuming excessive levels of iodine and MAF said this shows that the fortification policy has been effective in ensuring a balanced intake among children.

Iodine importance

Iodine is an element found in seawater, rocks and some types of soil that can be found in sea fish and shellfish as well as plant foods like cereals and grains. However, levels depend on the amount of iodine in the soil or sea.

The nutrient is linked to brain development and is therefore considered especially important for unborn babies, infants and young children. Deficiency of the nutrient can lead to health problems such as poor growth and development in children and thyroid diseases in the wider population.

The World Health Organisation said iodine deficiency is the world’s greatest single cause of preventable brain damage and mental impairment.

Research details

A sample of 530 breads was collected in April 2010 over three weeks from four New Zealand regions - Auckland, Central North Island, Christchurch and Dunedin.

The sample was categorised into eight bread groups – white, fibre white, wholemeal, mixed grain, rye, fruited, organic and crumpets – and the sodium and iodine content was measured by RJ Hill Laboratories.

Dietary intake of iodine in children aged 5-14 was then estimated using a Diamond computer program.

The research found that across New Zealand’s food industry, bread is now the highest iodine contributor, followed by milk and dairy products, grains and pasta, meats and eggs.

The ministry is set to commence a follow-up study this year to continue monitoring changes.

EU call for iodised salt policy

A recent study conducted by researchers at the  Swiss Federal Institute of Tehcnology Zurich and the International Council for the Control of Iodine Deficiency Disorders called for a common European Union policy on use of iodised salt across the food industry.

The study found that 44% of Europeans are deficient in the nutrient and lead author of the paper, Dr Maria Andersson said “coordinated actions for a common EU policy are needed, particularly for sale used by the food industry.”