Current trends of 24-h urinary iodine excretion in German schoolchildren and the importance of iodised salt in processed foods

Abstract

Worldwide, the iodisation of salt has clearly improved iodine status. In industrialised countries, iodised salt added to processed food contributes most to iodine supply. Median urinary iodine concentration fell below the WHO criteria for iodine sufficiency of 100 mg/l in 2007 -9. Salt, milk, fish and egg intake (g/d) were significant predictors of UIE (P,0·005); and the main sources of iodine were salt and milk (48 and 38 %, respectively). The present data hint at a beginning deterioration in the iodine status of German schoolchildren. A decreased use of iodised salt in industrially produced foods may be one possible reason for this development. Because of the generally known risks for cognitive impairment due to even mild iodine deficits in children, a more widespread use of iodised salt, especially in industrially processed foods, has to be promoted.

Examination of iodine status in the German population: an example for methodological pitfalls of the current approach of iodine status assessment

“…However, during the interim period between both surveys, neither iodine content in milk nor consumption of iodized salt fell noteworthy. Both milk and iodized salt are the most important iodine sources in Germany [24,25,28]. In accordance with a correspondingly constant micronutrient density for iodine in overall nutrition, we observed an approximately equal proportion of around 30 % of subjects with an iodine intake below the EAR in both DEGS and KiGGS studies.…”

“…So far, precise data on iodine contribution of relevant dietary iodine sources to overall iodine status exist only for children; in this age group, the contribution of iodized salt to total iodine intake amounts to about 50 % [24,37]. In the recent Swiss investigation (a country with comparable iodized salt legislation like Germany), iodized salt contributes with 54 % to total iodine intake also in adults.…”

“…All these urines were excluded for the generation of 24 Daily iodine intake was estimated from iodine excretion values by assuming a 10 % non-renal iodine loss (i.e., through sweat or feces [9]); accordingly, iodine intake was calculated by dividing estimated 24-h iodine excretion/day by 0.9.…”

Die DONALD Kohorte

“…So dient das Wiegeprotokoll (drei, vier beziehungsweise sieben Tage) häufig als Quasi-Referenzmethode bei der Entwicklung anderer Ernährungserhebungsmethoden [3,4]. Der 24-Stunden-Urin erlaubt die Bestimmung einer Reihe von Biomarkern, mit der die Nahrungszufuhr [5,6] oder Stoffwechselsituation des ganzen Tages abgebildet wird.…”

Iodine Status Assessment in Children: Spot Urine Iodine Concentration Reasonably Reflects True Twenty-Four–Hour Iodine Excretion Only When Scaled to Creatinine

“…The proportion of children below the EAR cutoff values (24) was estimated after considering a mean nonurinary iodine loss of 15% (25).…”