Concentration of iodine in iodized salt and estimation in school meals in a region of northeast Brazil

Improper levels or excess of iodine may present a greater risk to health, for this reason, this paper aims to assess the iodine content present in salt and estimate the iodine concentration in school meals in a Brazilian northeast region.

Six samples of different salt brands sold in the city of Lagarto, Sergipe, Brazil were gathered for analyzing iodate concentration. The amounts of salt added to meals of four schools in the city and the weight of the provided meals were recorded during two consecutive days of gathering, thus obtaining data to estimate the iodine content of these meals. The rest of the meals and the nutritional composition of school meals were analyzed. A questionnaire for participants on the perception of salt was applied. For data analysis, α = 5% was used.

The iodine concentration in all salt samples followed legislation (15 to 45 mg of iodine/kg of salt), with the average of iodine ranged between 26.5 ± 1.29 and 33.9 ± 2.49 mg/kg (p < 0.001). The estimated iodine content in consumed school meals was 0.025 mg (25 µg), in meals of schools A and C, it was 0.03 ± 0.02 mg, and to schools B and D, it was 0.02 ± 0.01 mg (p < 0.001). Percentages of rest of the meals greater than 10% were found and the assessed food preparation showed low caloric and nutritional values.

The iodine content is in accordance with the salt iodization policy in Brazil, and that the average iodine estimate in school meals was considered adequate for this population.