title: Are breast-fed infants and toddlers in New Zealand at risk of iodine deficiency?
abstract: OBJECTIVE
  This study assessed the iodine status of New Zealand infants and toddlers and explored factors that might influence their iodine status.
  
  
  METHODS
  A community-based, cross-sectional survey of 6- to 24-mo-old children was conducted in three cities in the South Island of New Zealand. Iodine status was determined by a casual urine sample. Breast-feeding mothers were asked to provide a breast milk sample for iodine determination. Caregivers collected a 3-d weighed diet record from their children to investigate associations between dietary patterns and urinary iodine excretion.
  
  
  RESULTS
  The median urinary iodine concentration for the group (n = 230) was 67 microg/L (interquartile range 37-115) with 37% (95% confidence interval 30.5-43.4) of children having a urinary iodine concentration lower than 50 microg/L. When children were classified by current feeding method, those children who were currently formula-fed had a significantly higher median urinary iodine concentration (99 microg/L) than did children who were currently breast-fed (44 microg/L; P < 0.000). The mean iodine concentration in breast milk was 22 microg/L (n = 39). After multivariate analysis using estimates from 3-d diet records, only percentage of energy from infant formula was significantly associated with urinary iodine concentration (P = 0.005).
  
  
  CONCLUSIONS
  This study found mild iodine deficiency in a group of New Zealand infants and toddlers. Children who consumed infant formula, which is fortified with iodine, had better iodine status than did children who were currently breast-fed because breast milk contained low levels of iodine.
authors.affiliation: Department of Human Nutrition, University of Otago, Dunedin, New Zealand.
authors.forename: Sheila A
authors.initials: SA
authors.lastname: Skeaff
authors.forename: Elaine L
authors.initials: EL
authors.lastname: Ferguson
authors.forename: Joanne E
authors.initials: JE
authors.lastname: McKenzie
authors.forename: Pierre
authors.initials: P
authors.lastname: Valeix
authors.forename: Rosalind S
authors.initials: RS
authors.lastname: Gibson
authors.forename: Christine D
authors.initials: CD
authors.lastname: Thomson
mesh_terms: D001942:Breast Feeding / Q000009:adverse effects* / Q000706:statistics & numerical data*; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D015930:Diet Records; D005260:Female; D006801:Humans; D007223:Infant; D007227:Infant Nutritional Physiological Phenomena / Q000502:physiology; D007455:Iodine / Q000172:deficiency* / Q000652:urine; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D009748:Nutrition Disorders / Q000453:epidemiology*; D009752:Nutritional Status / Q000502:physiology; D012044:Regression Analysis; D012307:Risk Factors; D011795:Surveys and Questionnaires
chemical_list: D007455:Iodine