Iodine concentration in canteen meals prepared with or without iodized salt

In each of two university canteens differing in the use (canteen A) or non-use (canteen B) of iodized salt for food preparation, 15 mostly equal lunch meals were collected for iodide and NaCl analysis. With similar NaCl content, the meals of canteen A contained on average 6.1 micrograms I/100 g ww (8.5 micrograms I/g NaCl) more I than the meals of canteen B. Total I intake by consumption of an average meal of canteen A was estimated as 56.5 +/- 24.1 micrograms (canteen B: 17.0 +/- 9.9 micrograms). Consequently, the use of iodized salt in central catering seems to play a more important role in a sufficient I intake than assumed so far.