Salt backlash blamed for deficiency

From: The Age, Australia - 16 Feb 2003

The anti-salt backlash and a reduction in the consumption of iodised salt may be partly responsible for the growing incidence of iodine deficiency among Australian children.

The Medical Journal of Australia will on Monday publish the latest evidence that iodine deficiency, which can cause learning difficulties and hearing impairment, is increasing in the Australian community.

The Victorian study found significant levels of iodine deficiency among a group of 600 Melbourne schoolchildren.

It comes after similar studies turned up deficiencies in children in Sydney and Tasmania.

Iodine is found in salt, iodised salt, seafood and seaweed. It is essential for the production of the thyroid hormones which control the metabolic activity of cells.

Lack of iodine can cause the thyroid gland to become underactive, resulting in slowness, tiredness, being overweight, constipation, coldness and a swelling of the neck known as goitre.

Severe deficiency can cause cretinism, intellectual disability, deaf muteness and severe physical disability.

However, with adequate diet or food supplements iodine is the single most preventable intellectual disability in the world.

Dr Margaret Zacharin and colleagues from the Royal Children's Hospital studied 607 Melbourne school children aged 11 to 18 in August 2001.

They found 76 per cent had some degree of iodine deficiency and 27 per cent had a moderate to severe deficiency.

Iodine levels were lower in girls, who were 2.5 times more likely to have an iodine deficiency than boys.

Overall, levels for boys and girls were below accepted levels set by the World Health Organisation.

Dr Zacharin said Australia was traditionally believed to have only isolated pockets of mild to moderate iodine deficiency.

Recent studies suggested this was a misconception, she said.

"Australia has been considered to be an iodine-replete country," she reports.

©2003 AAP