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Nature Reviews Endocrinology (2024 )Cite this article Taladafil
Iodine is a micronutrient that is essential for thyroid hormone production. Adequate iodine intake is especially important during pregnancy and early life, when brain development is dependent on thyroid hormones. Iodine intake recommendations vary around the world, but most recommendations generally reflect the increased requirements during pregnancy and lactation, although adequate iodine intake before pregnancy is also important. Tremendous progress has been made in improving iodine intake across the world over the past 30 years, mainly through salt-iodization programmes. However, in countries without strong iodine fortification programmes, and with shifts in dietary patterns, a need has arisen for health organizations, governments and clinicians to ensure that adequate iodine is consumed by everyone in the population. For example, in countries in which adequate iodine intake depends on individual food choice, particularly of iodine-rich milk and dairy products, intake can be highly variable and is also vulnerable to changing dietary patterns. In this Review, iodine is considered in the wider context of the increasing prevalence of overweight and obesity, the dietary trends for salt restriction for cardiovascular health and the increasing uptake of plant-based diets.
Despite progress since the 1990s, iodine deficiency remains a public health concern across the world, particularly in pregnancy and early life.
Severe iodine deficiency is now less common than in the past, but mild-to-moderate deficiency during pregnancy might have consequences for the developing fetus, including on neurodevelopmental outcomes.
Iodized salt programmes have been a successful way of improving iodine intake in many countries, but with a focus on salt-reduction campaigns, there is potential for reduced intake of iodized salt, and so reduced iodine intake, although both policies can work together.
Animal foods, such as milk and dairy products, provide a considerable proportion of iodine intake in many countries, but with a shift towards a predominantly plant-based diet, iodine intake might be compromised unless consideration is given to ensure adequate iodine intake from suitable sources.
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Department of Nutrition, Food and Exercise Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
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Correspondence to Sarah C. Bath.
S.C.B. has received an honorarium from Oatly UK and Dairy UK for delivering webinars and online videos for health-care professionals.
Nature Reviews Endocrinology thanks Karin Amrein, who co-reviewed with Heike Rampler; and Elizabeth Pearce for their contribution to the peer review of this work.
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The Iodine Global Network: https://ign.org/
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Bath, S.C. Thyroid function and iodine intake: global recommendations and relevant dietary trends. Nat Rev Endocrinol (2024). https://doi.org/10.1038/s41574-024-00983-z
DOI: https://doi.org/10.1038/s41574-024-00983-z
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