Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Perspective
  • Published:

Iodine nutrition: recent research and unanswered questions

European Journal of Clinical Nutrition volume 72, pages 1226–1228 (2018)Cite this article

Subjects

Iodine is a micronutrient required for the synthesis of thyroid hormone. Thyroid hormone regulates growth and metabolism, and is essential for normal neurodevelopment in utero and in early life. Sources of iodine in the diet include seafood, seaweed, dairy products, and eggs. Inadequate dietary iodine intakes result in a spectrum of adverse effects collectively known as iodine deficiency disorders (IDD). Severe maternal iodine deficiency in pregnancy increases the risk for stillbirth, miscarriage, perinatal and infant mortality, and congenital anomalies [1]. In the most severely iodine-deficient regions infants may be born with cretinism, a syndrome of severe intellectual impairment, growth impairment, and sometimes deafness. At any age, inadequate iodine intakes may result in hypothyroidism and goiter.

Dietary iodine requirements change over the course of the lifespan (Table 1). Pregnant women require higher iodine intakes than nonpregnant adults because of increased thyroid hormone synthesis, some transfer of iodine to the fetus (which requires iodine for its own thyroid hormone synthesis starting around mid-gestation), and because increased glomerular filtration rates result in increased passive losses of iodine in the urine [2, 3]. Women who are breastfeeding require increased iodine intakes because iodine is actively secreted into breast milk [4], where it is critically important as a nutrition source for the breastfed infant.

Table 1 Recommended daily iodine intakes by life stage
Full size table

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

References

  1. Zimmermann MB, Boelaert K. Iodine deficiency and thyroid disorders. Lancet Diabetes Endocrinol. 2015;3:286–95.

    Article  CAS  Google Scholar 

  2. Glinoer D. The importance of iodine nutrition during pregnancy. Public Health Nutr. 2007;10:1542–6.

    Article  Google Scholar 

  3. Dafnis E, Sabatini S. The effect of pregnancy on renal function: physiology and pathophysiology. Am J Med Sci. 1992;303:184–205.

    Article  CAS  Google Scholar 

  4. Tazebay UH, Wapnir IL, Levy O, Dohan O, Zuckier LS, Zhao QH, et al. The mammary gland iodide transporter is expressed during lactation and in breast cancer. Nat Med. 2000;6:871–8.

    Article  CAS  Google Scholar 

  5. Leung AM, Braverman LE. Consequences of excess iodine. Nat Rev Endocrinol. 2014;10:136–42.

    Article  CAS  Google Scholar 

  6. Eng PH, Cardona GR, Fang SL, Previti M, Alex S, Carrasco N, et al. Escape from the acute Wolff–Chaikoff effect is associated with a decrease in thyroid sodium/iodide symporter messenger ribonucleic acid and protein. Endocrinology. 1999;140:3404–10.

    Article  CAS  Google Scholar 

  7. Theodoropoulos T, Braverman LE, Vagenakis AG. Iodide-induced hypothyroidism: a potential hazard during perinatal life. Science. 1979;205:502–3.

    Article  CAS  Google Scholar 

  8. Zimmermann MB, Hess SY, Molinari L, De Benoist B, Delange F, Braverman LE, et al. New reference values for thyroid volume by ultrasound in iodine-sufficient schoolchildren: a World Health Organization/Nutrition for Health and Development Iodine Deficiency Study Group Report. Am J Clin Nutr. 2004;79:231–7.

    Article  CAS  Google Scholar 

  9. König F, Andersson M, Hotz K, Aeberli I, Zimmermann MB. Ten repeat collections for urinary iodine from spot samples or 24-hour samples are needed to reliably estimate individual iodine status in women. J Nutr. 2011;141:2049–54.

    Article  Google Scholar 

  10. Kimball OP, Marine D. The prevention of simple goiter in man: second paper. Arch Intern Med. 1918;44:41–44.

    Article  Google Scholar 

  11. Pharoah PO, Buttfield IH, Hetzel BS. The effect of iodine prophylaxis on the incidence of endemic cretinism. Adv Exp Med Biol. 1972;30:201–21.

    CAS  PubMed  Google Scholar 

  12. Qian M, Wang D, Watkins WE, Gebski V, Yan YQ, Li M, et al. The effects of iodine on intelligence in children: a meta-analysis of studies conducted in China. Asia Pac J Clin Nutr. 2005;14:32–42.

    CAS  PubMed  Google Scholar 

  13. Bougma K, Aboud FE, Harding KB, Marquis GS. Iodine and mental development of children 5 years old and under: a systematic review and meta-analysis. Nutrients. 2013;5:1384–416.

    Article  CAS  Google Scholar 

  14. Bath SC, Steer CD, Golding J, Emmett P, Rayman MP. Effect of inadequate iodine status in UK pregnant women on cognitive outcomes in their children: results from the Avon Longitudinal Study of Parents and Children (ALSPAC). Lancet. 2013;382:331–7.

    Article  CAS  Google Scholar 

  15. Hynes KL, Otahal P, Hay I, Burgess JR. Mild iodine deficiency during pregnancy is associated with reduced educational outcomes in the offspring: 9-year follow-up of the gestational iodine cohort. J Clin Endocrinol Metab. 2013;98:1954–62.

    Article  CAS  Google Scholar 

  16. Abel MH, Caspersen IH, Meltzer HM, Haugen M, Brandlistuen RE, Aase H, et al. Suboptimal maternal iodine intake Is associated with impaired child neurodevelopment at 3 years of age in the Norwegian mother and child cohort study. J Nutr. 2017;147:1314–24.

    Article  CAS  Google Scholar 

  17. Abel MH, Ystrom E, Caspersen IH, Meltzer HM, Aase H, Torheim LE, et al. Maternal iodine intake and offspring attention deficit/hyperactivity disorder: results from a large prospective cohort study. Nutrients. 2017;13:9. pii: E1239

    Google Scholar 

  18. Mills JL, Buck Louis GM, Kannan K, Weck J, Wan Y, Maisog J, et al. Delayed conception in women with low-urinary iodine concentrations: a population-based prospective cohort study. Hum Reprod. https://doi.org/10.1093/humrep/dex379, 2018. e-pub ahead of print 2018.

    Article  CAS  Google Scholar 

  19. Zimmermann MB, Aeberli I, Andersson M, Assey V, Yorg JA, Jooste P. Thyroglobulin is a sensitive measure of both deficient and excess iodine intakes in children and indicates no adverse effects on thyroid function in the UIC range of 100-299 μg/L: a UNICEF/ICCIDD study group report. J Clin Endocrinol Metab. 2013;98:1271–80.

    Article  CAS  Google Scholar 

  20. Stinca S, Andersson M, Weibel S, Herter-Aeberli I, Fingerhut R, Gowachirapant S, et al. Dried blood spot thyroglobulin as a biomarker of iodine status in pregnant women. J Clin Endocrinol Metab. 2017;102:23–32.

    PubMed  Google Scholar 

  21. Dold S, Zimmermann MB, Aboussad A, Cherkaoui M, Jia Q, Jukic T, et al. Breast milk iodine concentration is a more accurate biomarker of iodine status than urinary iodine concentration in exclusively breastfeeding women. J Nutr. 2017;147:528–37.

    Article  CAS  Google Scholar 

  22. Wong EM, Sullivan KM, Perrine CG, Rogers LM, Peña-Rosas JP. Comparison of median urinary iodine concentration as an indicator of iodine status among pregnant women, school-age children, and nonpregnant women. Food Nutr Bull. 2011;32:206–12.

    Article  Google Scholar 

  23. Dold S, Zimmermann MB, Jukic T, Kusic Z, Jia Q, Sang Z, et al. Universal salt iodization provides sufficient dietary iodine to achieve adequate iodine nutrition during the first 1000 days: a cross-sectional multicenter study. J Nutr. 2018;148:587–98.

    Article  Google Scholar 

  24. Bouhouch RR, Bouhouch S, Cherkaoui M, Aboussad A, Stinca S, Haldimann M, et al. Direct iodine supplementation of infants versus supplementation of their breastfeeding mothers: a double-blind, randomised, placebo-controlled trial. Lancet Diabetes Endocrinol. 2014;2:197–209.

    Article  CAS  Google Scholar 

  25. Zhou SJ, Skeaff SA, Ryan P, Doyle LW, Anderson PJ, Kornman L, et al. The effect of iodine supplementation in pregnancy on early childhood neurodevelopment and clinical outcomes: results of an aborted randomised placebo-controlled trial. Trials. 2015;16:563-1–563-9.

    Google Scholar 

  26. Gowachirapant S, Jaiswal N, Melse-Boonstra A, Galetti V, Stinca S, Mackenzie I. Effect of iodine supplementation in pregnant women on child neurodevelopment: a randomised, double-blind, placebo-controlled trial. Lancet Diabetes Endocrinol. 2017;5:853–63.

    Article  CAS  Google Scholar 

  27. Chen W, Li X, Wu Y, Bian J, Shen J, et al. Associations between iodine intake, thyroid volume, and goiter rate in school-aged Chinese children from areas with high iodine drinking water concentrations. Am J Clin Nutr. 2017;105:228–33.

    Article  CAS  Google Scholar 

  28. Shi X, Han C, Li C, Mao J, Wang W, Xie X, et al. Optimal and safe upper limits of iodine intake for early pregnancy in iodine-sufficient regions: a cross-sectional study of 7190 pregnant women in China. J Clin Endocrinol Metab. 2015;100:1630–8.

    Article  CAS  Google Scholar 

  29. Leung AM, Pearce EN, Braverman LE. Environmental perchlorate exposure: potential adverse thyroid effects. Curr Opin Endocrinol Diabetes Obes. 2014;21:372–6.

    Article  CAS  Google Scholar 

  30. World Health Organization. Salt reduction and iodine fortification strategies in public health: report of a joint technical meeting convened by the World Health Organization and The George Institute for Global Health in collaboration with the International Council for the Control of Iodine Deficiency Disorders Global Network, Sydney, Australia, 2013. Geneva, Switzerland: World Health Organization; 2014.

  31. Institute of Medicine. Dietary reference intakes for vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc. Washington, DC: National Academy Press; 2001.

    Google Scholar 

  32. WHO, UNICEF, and ICCIDD. Assessment of the iodine deficiency disorders and monitoring their elimination. WHO/NHD/01.1. 3rd ed. Geneva: World Health Organization; 2007.

Download references

Author information

Authors and Affiliations

  1. Section of Endocrinology, Diabetes, and Nutrition, Boston University School of Medicine, 720 Harrison Ave, Suite 8100, Boston, MA, 02118, USA

    Elizabeth N. Pearce

Authors
  1. Elizabeth N. Pearce
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Elizabeth N. Pearce.

Ethics declarations

Conflict of interest

The authors declare that they have no conflict of interest.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Pearce, E.N. Iodine nutrition: recent research and unanswered questions. Eur J Clin Nutr 72, 1226–1228 (2018). https://doi.org/10.1038/s41430-018-0226-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41430-018-0226-7

This article is cited by

Search

Advanced search

Quick links