title: Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt.
abstract: Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8-10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC), a fingerpick blood sample for Thyroglobulin (Tg) concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ). The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415) was 116 μg/L (females 106 μg/L, males 131 μg/L) indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100-199 μg/L). The median Tg concentration was 8.7 μg/L, which was <10 μg/L confirming adequate iodine status. There was a significant difference in UIC by sex (p = 0.001) and ethnicity (p = 0.006). The mean iodine intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate.
authors.affiliation: Department of Human Nutrition, University of Otago, Dunedin 9054, New Zealand. emmajones.nz@gmail.com.
authors.forename: Emma
authors.initials: E
authors.lastname: Jones
authors.affiliation: Department of Human Nutrition, University of Otago, Dunedin 9054, New Zealand. rachael.mclean@otago.ac.nz.|Department of Preventive and Social Medicine, University of Otago, Dunedin 9054, New Zealand. rachael.mclean@otago.ac.nz.
authors.forename: Rachael
authors.initials: R
authors.lastname: McLean
authors.affiliation: Department of Human Nutrition, University of Otago, Dunedin 9054, New Zealand. briardavies@gmail.com.
authors.forename: Briar
authors.initials: B
authors.lastname: Davies
authors.affiliation: Department of Human Nutrition, University of Otago, Dunedin 9054, New Zealand. rkhawkins039@gmail.com.
authors.forename: Rochelle
authors.initials: R
authors.lastname: Hawkins
authors.affiliation: Department of Human Nutrition, University of Otago, Dunedin 9054, New Zealand. evameiklejohn@gmail.com.
authors.forename: Eva
authors.initials: E
authors.lastname: Meiklejohn
authors.affiliation: Department of Human Nutrition, University of Otago, Dunedin 9054, New Zealand. zhengfeei.ma@postgrad.otago.ac.nz.
authors.forename: Zheng Feei
authors.initials: ZF
authors.lastname: Ma
authors.affiliation: Department of Human Nutrition, University of Otago, Dunedin 9054, New Zealand. sheila.skeaff@otago.ac.nz.
authors.forename: Sheila
authors.initials: S
authors.lastname: Skeaff
mesh_terms: D001939:Bread / Q000032:analysis*; D002648:Child; D002664:Child Nutritional Physiological Phenomena; D003430:Cross-Sectional Studies; D005260:Female; D005527:Food, Fortified; D006801:Humans; D007455:Iodine / Q000008:administration & dosage / Q000097:blood / Q000737:chemistry / Q000172:deficiency* / Q000652:urine*; D008297:Male; D009520:New Zealand; D009749:Nutrition Surveys; D012959:Socioeconomic Factors; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage*; D011795:Surveys and Questionnaires; D013954:Thyroglobulin / Q000097:blood / Q000652:urine
chemical_list: D017673:Sodium Chloride, Dietary; C034024:iodized salt; D013954:Thyroglobulin; D007455:Iodine
keywords: New Zealand; children; deficiency; fortification; iodine; iodised salt