title: Iodine excretion has decreased in Denmark between 2004 and 2010--the importance of iodine content in milk.
abstract: Fortification with the essential trace element iodine is widespread worldwide. In the present study, results on iodine excretion and intake of iodine-rich foods from a cross-sectional study carried out in 2004-5, 4 to 5 years after the implementation of mandatory iodine fortification, were compared with data in a study carried out in 2008-10. The 2008-10 study was a follow-up of a cross-sectional study carried out before iodine fortification was implemented. Participants in the cross-sectional studies were randomly selected. Both studies were carried out in the cities of Aalborg and Copenhagen in Denmark. The median urinary iodine concentration decreased in women from 97 μg/l (n 2862) to 78 μg/l (n 2041) (P< 0.001). The decrease persisted after adjustment for age, city and education, and if expressed as estimated 24 h iodine excretion. The prevalence of users of iodine containing dietary supplements increased from 29.4 to 37.3 % (P< 0.001). The total fluid intake increased in women (P< 0.001), but the intake of other iodine-rich foods did not change. The median urinary iodine concentration did not change in men (114 μg/l (n 708) and 107 μg/l (n 424), respectively), while the total fluid intake decreased (P= 0.001). Iodine content was measured in milk sampled in 2000-1 and in 2013. The iodine content was lower in 2013 (12 (sd 3) μg/100 g) compared with that in 2000-1 (16 (sd 6) μg/100 g) (P< 0.001). In conclusion, iodine excretion in women has decreased below the recommended level. The reason might probably, at least partly, be a decreased content of iodine in milk.
authors.affiliation: Division of Nutrition, National Food Institute, Technical University of Denmark,Mørkhøj Bygade 19,2860Søborg,Denmark.
authors.forename: Lone B
authors.initials: LB
authors.lastname: Rasmussen
authors.affiliation: Department of Endocrinology,Aalborg University Hospital and Department of Clinical Medicine, Aalborg University,Aalborg,Denmark.
authors.forename: Allan
authors.initials: A
authors.lastname: Carlé
authors.affiliation: Research Centre for Prevention and Health, The Capital Region of Denmark,Glostrup,Denmark.
authors.forename: Torben
authors.initials: T
authors.lastname: Jørgensen
authors.affiliation: Division of Food Chemistry, National Food Institute, Technical University of Denmark,Søborg,Denmark.
authors.forename: Pia
authors.initials: P
authors.lastname: Knuthsen
authors.affiliation: Department of Endocrinology,Aalborg University Hospital and Department of Clinical Medicine, Aalborg University,Aalborg,Denmark.
authors.forename: Anne
authors.initials: A
authors.lastname: Krejbjerg
authors.affiliation: Department of Endocrinology and Gastroenterology,Bispebjerg University Hospital,Copenhagen,Denmark.
authors.forename: Hans
authors.initials: H
authors.lastname: Perrild
authors.affiliation: Research Centre for Prevention and Health, The Capital Region of Denmark,Glostrup,Denmark.
authors.forename: Lena
authors.initials: L
authors.lastname: Bjergved
authors.affiliation: Division of Food Chemistry, National Food Institute, Technical University of Denmark,Søborg,Denmark.
authors.forename: Jens J
authors.initials: JJ
authors.lastname: Sloth
authors.affiliation: Department of Endocrinology,Aalborg University Hospital and Department of Clinical Medicine, Aalborg University,Aalborg,Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Laurberg
authors.affiliation: Department of Gastroenterology,Slagelse Hospital,Slagelse,Denmark.
authors.forename: Lars
authors.initials: L
authors.lastname: Ovesen
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D003430:Cross-Sectional Studies; D003718:Denmark; D004032:Diet; D019587:Dietary Supplements / Q000706:statistics & numerical data; D002149:Energy Intake; D005260:Female; D005527:Food, Fortified; D006801:Humans; D007455:Iodine / Q000008:administration & dosage / Q000172:deficiency / Q000652:urine*; D008297:Male; D008875:Middle Aged; D008892:Milk / Q000737:chemistry*; D012737:Sex Factors
chemical_list: D007455:Iodine