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Most bread is set to become iodine fortified over the next 18 months in a bid to combat New Zealanders' growing problem of iodine deficiency.
"For some years, the amount of iodine people are consuming has been dropping," said New Zealand Food Safety Authority (NZFSA) assistant director Jenny Reid .
Reasons included New Zealand's naturally low soil iodine levels, the growing popularity of sea and rock salts, a general reduction in the amount of salt consumed and the move away from the use of iodine-based disinfectants in industry and the home.
Ms Reid said NZFSA's last Total Diet Survey highlighted the problem, with New Zealanders' iodine levels now far lower than those of people in other nations.
"Iodine levels that are too low irreversibly impair the development of intelligence in children, beginning in the womb and continuing through childhood. Low iodine levels in adults are also a concern, with severe cases leading to goitre," she said.
Food Standards Australia New Zealand has decided to make it mandatory for bread manufacturers to replace non-iodised salt in breads with iodised salt. Unleavened bread - such as pita and tortilla - and organic products are exempt.
Iodine is an essential nutrient for humans and iodine deficiency has been linked to a host of problems. Although iodine is only needed in very small amounts, it is vital for thyroid hormones to maintain the body's metabolic state and to support normal growth and development in children.
As iodine is essential for normal brain development, it is particularly important that unborn babies and young children have adequate intakes.
Severe cases of iodine deficiency can lead to stunted growth and mental retardation in children.
Foods naturally rich in iodine include seafood (fish, shellfish and seaweed), milk and milk products, seameal custard and eggs.
Another source of iodine is iodised table salt. The Ministry of Health recommends limiting overall salt intake to reduce the risk of stroke and heart disease, but that if salt is used for cooking and at the table it should be iodised.
Bread manufacturers have until September 2009 to comply with the new regulation to allow time to make the required changes to manufacturing and labelling. It will also give the salt industry time to increase the production of iodised salt.
- NZPA
