Assessment of iodine fortification of salt in the Danish population

Eur J Nutr. 2022 Sep;61(6):2939-2951. doi: 10.1007/s00394-022-02826-x. Epub 2022 Mar 21.


Purpose: We assessed the effect of the current iodine fortification level (20 µg/g household salt and salt included in bread and bakery products) on inadequate and excessive intake in the general Danish population. Intake models with/without the contribution from food supplements and effects of excluding specific food groups were evaluated.

Method: Data from the Danish National Survey of Dietary Habits and Physical Activity in 2011-13 (N = 3946, aged 4-75 years) stratified by age-group and sex were used to estimate habitual dietary iodine intakes, and compared with established dietary reference values.

Results: The proportion with an estimated inadequate iodine intake was ≤ 3% for males and ≤ 5% for females, except for 15-17-year-old girls, where the probable prevalence of an inadequate intake was 11%. Including the contribution from food supplements gave similar results (10%). High intakes (as defined by 95th percentile) from food sources generally did not exceed the tolerable upper intake level (UL). However, for the youngest age-groups (4-6-year-old boys/girls and 7-10-year-old boys), the 95th percentiles exceeded the UL with 11%, 4% and 7%, respectively, when food supplements were included in the estimates. Especially exclusion of dairy products and bread led to an inadequate intake for both boys and girls.

Conclusion: The current fortification level may provide an inadequate iodine intake for some females and on the other hand lead to excessive intakes in the youngest age-groups. The study shows the importance of choosing iodine-rich alternatives when excluding major sources of iodine in the Danish diet.

Keywords: Diet; Dietary supplement; Fortification; Household salt; Iodine; Modelling.

MeSH terms

  • Adolescent
  • Child
  • Child, Preschool
  • Denmark / epidemiology
  • Diet Surveys
  • Female
  • Food, Fortified
  • Humans
  • Iodides
  • Iodine*
  • Male
  • Sodium Chloride, Dietary


  • Iodides
  • Sodium Chloride, Dietary
  • Iodine