Prevalence of iodine inadequacy in Switzerland assessed by the estimated average requirement cut-point method in relation to the impact of iodized salt

Public Health Nutr. 2015 Jun;18(8):1333-42. doi: 10.1017/S1368980014002018. Epub 2014 Sep 18.


Objective: To assess the iodine status of Swiss population groups and to evaluate the influence of iodized salt as a vector for iodine fortification.

Design: The relationship between 24 h urinary iodine and Na excretions was assessed in the general population after correcting for confounders. Single-day intakes were estimated assuming that 92 % of dietary iodine was excreted in 24 h urine. Usual intake distributions were derived for male and female population groups after adjustment for within-subject variability. The estimated average requirement (EAR) cut-point method was applied as guidance to assess the inadequacy of the iodine supply.

Setting: Public health strategies to reduce the dietary salt intake in the general population may affect its iodine supply.

Subjects: The study population (1481 volunteers, aged ≥15 years) was randomly selected from three different linguistic regions of Switzerland.

Results: The 24 h urine samples from 1420 participants were determined to be properly collected. Mean iodine intakes obtained for men (n 705) and women (n 715) were 179 (sd 68.1) µg/d and 138 (sd 57.8) µg/d, respectively. Urinary Na and Ca, and BMI were significantly and positively associated with higher iodine intake, as were men and non-smokers. Fifty-four per cent of the total iodine intake originated from iodized salt. The prevalence of inadequate iodine intake as estimated by the EAR cut-point method was 2 % for men and 14 % for women.

Conclusions: The estimated prevalence of inadequate iodine intake was within the optimal target range of 2-3 % for men, but not for women.

Keywords: Iodized salt.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Female
  • Humans
  • Iodine / administration & dosage
  • Iodine / deficiency*
  • Iodine / urine
  • Linear Models
  • Male
  • Middle Aged
  • Nutritional Requirements*
  • Nutritional Status
  • Prevalence
  • Sodium / urine
  • Sodium Chloride, Dietary / administration & dosage*
  • Switzerland / epidemiology
  • Young Adult


  • Sodium Chloride, Dietary
  • iodized salt
  • Iodine
  • Sodium