Mild iodine deficiency in a sample of New Zealand schoolchildren.
OBJECTIVE
To assess the iodine status of New Zealand schoolchildren.


METHODS
A proportionate to population size school-based cluster survey was used to randomly select children from two cities. The indicators used to assess iodine status were urinary iodine, as determined in a casual urine sample, and thyroid volume, as measured by ultrasonography. A qualitative food frequency questionnaire designed to ascertain frequency of consumption over the previous 3 months of foods or food groups that are good sources of dietary iodine, including iodized salt, was administered to each child.


METHODS
Dunedin and Wellington, New Zealand.


METHODS
Three-hundred children aged 8-10 y from 30 schools.


RESULTS
The median urinary iodine concentration of the children was 6.6 micro g/dl (interquartile range, 4.5-9.1). The percentage of children who had urinary iodine levels less than 5 micro g/dl was 31.4 (95% confidence interval (CI), 24.2-38.6). Comparison of thyroid volume with 2001 World Health Organization age/sex-specific and age/BSA-specific cut-off values resulted in a goitre prevalence of 11.3% (95% CI, 7.6-15.1) and 12.0% (95% CI, 7.9-16.1), respectively. Almost 30% of the children's caregivers did not use iodized salt in cooking and 51% of the children did not use iodized salt at the table.


CONCLUSIONS
Mild iodine deficiency was found in this sample of children. Iodized table salt may no longer be making a significant contribution to the iodine intakes of New Zealand children.
Skeaff
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SA
Department of Human Nutrition, University of Otago, Dunedin, New Zealand. sheila.skeaff@stonebow.otago.ac.nz
Thomson
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CD
Gibson
R S
RS
D002648:Child; D016000:Cluster Analysis; D016001:Confidence Intervals; D005247:Feeding Behavior; D005260:Female; D006042:Goiter / Q000453:epidemiology* / Q000652:urine; D006306:Health Surveys; D006801:Humans; D007455:Iodine / Q000008:administration & dosage* / Q000172:deficiency* / Q000652:urine*; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D009752:Nutritional Status; D016017:Odds Ratio; D015995:Prevalence; D012574:Schools; D012959:Socioeconomic Factors; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage*; D011795:Surveys and Questionnaires; D013961:Thyroid Gland / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D014463:Ultrasonography
D017673:Sodium Chloride, Dietary; C034024:iodized salt; D007455:Iodine