Loading...
Publication
Evaluation of iodine content in Portuguese primary school meals after mandatory iodization program
Advisor(s)
Abstract(s)
Iodine is an essential trace element in human diets. Iodine deficiency is the most common cause of preventable mental impairment. There is a widespread deficiency of iodine in school-age children, in Portugal. The aim of this study was to monitor the real content of iodine in school meals provided to primary school children, after the introduction of iodized salt.
A sampling plan comprised the collection of 300 samples from school canteens, organized into three groups. Group I contained 124 samples from primary schools across the Lisbon metropolitan area. Group II had 12 samples from a pilot school used as a reference for real iodine content, since they were effectively cooked with iodized salt. Group III was constituted by 124 samples cooked without iodized salt.
The determination of iodine content was performed using inductively coupled plasma-mass spectrometry (ICP-MS) after alkaline extraction with TMAH (tetramethylammonium hydroxide) in a graphite hotblock system.
The results showed a wide range in the concentration of iodine. The content in Group I varied from 5.3 μg/100 g in pasta to 52 μg/100 g in cod. In Group II the highest value (32 μg/100 g) was found in soup. Meat, in particular samples from Group III, presented the lowest values (<1.9 μg/100). The ratio between Group I and Group III was used to estimate the effectiveness of the program. The highest difference was found in fish while the lowest was determined in soup. The difference between iodine content in Group I and Group II was used to monitor the use of iodized salt in the schools from the Lisbon metropolitan area.
This study demonstrates that the determination of iodine content, in foods cooked with and without iodized salt, is an appropriate approach to evaluate fortification programs and risks of both inadequate and excess iodine intake.
Description
Keywords
iodine School Meals Composição dos Alimentos Avaliação do Risco
Pedagogical Context
Citation
Publisher
Instituto Nacional de Saúde Doutor Ricardo Jorge, IP