Consequences of excess iodine

Journal name:
Nature Reviews Endocrinology
Volume:
10,
Pages:
136–142
Year published:
DOI:
doi:10.1038/nrendo.2013.251
Published online

Abstract

Iodine is a micronutrient that is essential for the production of thyroid hormones. The primary source of iodine is the diet via consumption of foods that have been fortified with iodine, including salt, dairy products and bread, or that are naturally abundant in the micronutrient, such as seafood. Recommended daily iodine intake is 150 µg in adults who are not pregnant or lactating. Ingestion of iodine or exposure above this threshold is generally well-tolerated. However, in certain susceptible individuals, including those with pre-existing thyroid disease, the elderly, fetuses and neonates, or patients with other risk factors, the risk of developing iodine-induced thyroid dysfunction might be increased. Hypothyroidism or hyperthyroidism as a result of supraphysiologic iodine exposure might be either subclinical or overt, and the source of the excess iodine might not be readily apparent.

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Author information

Affiliations

  1. Division of Endocrinology, Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, VA Greater Los Angeles Healthcare System, 11301 Wilshire Boulevard (111D), Los Angeles, CA 90073, USA.

    • Angela M. Leung
  2. Section of Endocrinology, Diabetes, and Nutrition, Department of Medicine, Boston University School of Medicine, 88 East Newton Street, Evans 201, Boston, MA 02118, USA.

    • Lewis E. Braverman

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Both authors contributed equally to all aspects of this manuscript.

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The authors declare no competing interests.

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Author details

  • Angela M. Leung

    Angela M. Leung, MD, MSc, is Assistant Clinical Professor of Medicine in the Division of Endocrinology, University of California Los Angeles, USA. She received a BA at Occidental College, USA, an MD from Boston University School of Medicine, USA, and an MSc from Boston University School of Public Health, USA. She completed her medicine residency and endocrinology fellowship training at Boston University School of Medicine and Boston Medical Center. Her clinical and research interests are in iodine nutrition, thyroid dysfunction and thyroid cancer, women and infant health, and environmental exposures that affect iodine nutrition.

  • Lewis E. Braverman

    Lewis E. Braverman, MD, is Professor of Medicine in the Section of Endocrinology, Diabetes, and Nutrition, Boston University School of Medicine, USA. He received his undergraduate degree from Harvard College, USA, and his MD from Johns Hopkins, USA. His residency and fellowship training was completed at the Thorndike Memorial Laboratory, Harvard Medical School, USA. Dr Braverman has held many leadership roles in national endocrine organizations and has published extensively in various aspects of thyroid physiology and pathophysiology.

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