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Minerals, trace elements, Vit. D and bone health

Daily iodine intake and the impact of salt reduction on iodine prophylaxis in the Italian population

Abstract

Background/objectives:

Salt iodization is one of the preferred strategies to eradicate iodine-deficiency disorders worldwide. The aim of this study was (i) to estimate the daily iodine intake in the Italian population, (ii) to verify whether the recently recommended salt intake of 5 g/day in adults and less in children may be sufficient to achieve the adequate daily iodine intake, (iii) to estimate the contribution of iodine-enriched vegetables to the total daily iodine intake.

Subjects/methods:

The content of iodine has been evaluated in 288 food samples highly representative of Italian eating habits. The contribution of foods and iodized salt to the total daily iodine intake was estimated in adults, adolescents, and children on the basis of available nationwide data of food consumption.

Results:

The total daily iodine intake owing to food and uniodized salt consumption resulted lower than the daily requirement in all age groups. With a daily consumption of 5 g of salt iodized at 30 mg/kg, the estimated daily iodine intake resulted within the range of optimal iodine intake in all age groups. In children the recommended iodine intake is achieved with a daily consumption of 3 g of iodized salt. Moreover, the daily iodine intake significantly increased in all age groups if the consumption of iodine-enriched vegetables was considered in substitution of non iodine-enriched ones.

Conclusions:

Our study suggests that the recommended quantities of salt, if iodized at 30 mg/kg, are sufficient to achieve the adequate daily iodine intake both in adults and children.

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Acknowledgements

We thank Daniela Rotondi for her technical assistance. This research was supported by the Istituto Superiore di Sanità grant No. 3AQC.

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Correspondence to A Olivieri.

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Pastorelli, A., Stacchini, P. & Olivieri, A. Daily iodine intake and the impact of salt reduction on iodine prophylaxis in the Italian population. Eur J Clin Nutr 69, 211–215 (2015). https://doi.org/10.1038/ejcn.2014.206

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  • DOI: https://doi.org/10.1038/ejcn.2014.206

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