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Iodine nutrition in pregnant and breastfeeding women: sufficiency, deficiency, and supplementation

  • Hossein DelshadEmail author
  • Fereidoun Azizi
Review Article


Iodine is a micronutrient used by the thyroid gland to produce thyroid hormones, which manage different aspects of body metabolism. Humans depend on exogenous sources of iodine to maintain the normal concentration of thyroid hormones. Pregnancy alters iodine turnover and is associated with significant changes in thyroid function. Daily iodine requirement during pregnancy increases to 250 μg, compared with 150 μg for nonpregnant women. According to recent guidelines of scientific organizations, to improve maternal thyroid status and to prevent child neurocognitive defects, all pregnant and breastfeeding women should take 150 μg of iodine supplementation, not only in iodine-deficient regions but also in iodine-sufficient areas. However, some recent studies have confirmed that iodine supplementation of mildly iodine-deficient pregnant women has no clear benefits as concerns maternal thyroid function or child neurodevelopment.


Iodine supplementation Pregnancy Lactation Iodine deficiency Iodine status 



The authors wish to acknowledge Ms. Niloofar Shiva for her critical editing of the English grammar and syntax of the manuscript.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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© Hellenic Endocrine Society 2019

Authors and Affiliations

  1. 1.Micronutrient Research Office, Endocrine Research Center, Research Institute for Endocrine SciencesShahid Beheshti University of Medical SciencesTehranIslamic Republic of Iran
  2. 2.Endocrine Research Center, Research Institute for Endocrine SciencesShahid Beheshti University of Medical SciencesTehranIslamic Republic of Iran

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