Nutritional Supplement

Iodine

Where to Find It

Seafood , iodized salt, and sea vegetables—for example, kelp—are high in iodine. Processed food may contain added iodized salt. Iodine is frequently found in dairy products. Vegetables grown in iodine-rich soil also contain this mineral.

Best Form to Take

Common iodine supplement preparations include potassium iodide, potassium iodate, and a combination of iodine and potassium iodide, otherwise known as Lugol’s solution.15

How to Use It

Since the introduction of iodized salt, iodine supplements are unnecessary and not recommended for most people. For strict vegetarians who avoid salt and sea vegetables, 150 mcg per day is commonly supplemented. This amount is adequate to prevent a deficiency and higher amounts are not necessary.

References

1. Bath SC, Steer CD, Golding J, et al. 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.

2. Vermiglio F, Lo Presti VP, Moleti M, et al. Attention deficit and hyperactivity disorders in the offspring of mothers exposed to mild-moderate iodine deficiency: a possible novel iodine deficiency disorder in developed countries. J Clin Endocrinol Metab 2004;89:6054-60.

3. Vermiglio F, Lo Presti VP, Moleti M, et al. Attention deficit and hyperactivity disorders in the offspring of mothers exposed to mild-moderate iodine deficiency: a possible novel iodine deficiency disorder in developed countries. J Clin Endocrinol Metab 2004;89:6054-60.

4. Krouse TB, Eskin BA, Mobini J. Age-related changes resembling fibrocystic disease in iodine-blocked rat breasts. Arch Pathol Lab Med 1979;103:631-4.

5. Ghent WR, Eskin BA, Low DA, Hill L. Iodine replacement in fibrocystic disease of the breast. Can J Surg 1993;36:453-60.

6. Bath SC, Steer CD, Golding J, et al. 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.

7. Vermiglio F, Lo Presti VP, Moleti M, et al. Attention deficit and hyperactivity disorders in the offspring of mothers exposed to mild-moderate iodine deficiency: a possible novel iodine deficiency disorder in developed countries. J Clin Endocrinol Metab 2004;89:6054-60.

8. Vermiglio F, Lo Presti VP, Moleti M, et al. Attention deficit and hyperactivity disorders in the offspring of mothers exposed to mild-moderate iodine deficiency: a possible novel iodine deficiency disorder in developed countries. J Clin Endocrinol Metab 2004;89:6054-60.

9. Vermiglio F, Lo Presti VP, Moleti M, et al. Attention deficit and hyperactivity disorders in the offspring of mothers exposed to mild-moderate iodine deficiency: a possible novel iodine deficiency disorder in developed countries. J Clin Endocrinol Metab 2004;89:6054-60.

10. Thilly CH, Swennen B, Bourdoux P, et al. The epidemiology of iodine-deficiency disorders in relation to goitrogenic factors and thyroid-stimulating-hormone regulation. Am J Clin Nutr 1993;57(2 Suppl):267S-70S.

11. Delange F. Risks and benefits of iodine supplementation. Lancet 1998;351:923-4.

12. Contempre B, Dumont JE, Ngo B, et al. Effect of selenium supplementation in hypothyroid subjects of an iodine and selenium deficient area: the possible danger of indiscriminate supplementation of iodine-deficient subjects with selenium. J Clin Endocrinol Metab 1991;73:213-5.

13. Chow CC, Phillips DIW, Lazarus JH, Parkes AB. Effect of low dose iodide supplementation on thyroid function in potentially susceptible subjects: are dietary iodide levels in Britain acceptable? Clin Endocrinol 1991;34:413-6.

14. Stewart JC, Vidor GI. Thyrotoxicosis induced by iodine contamination of food: a common unrecognized condition? Br Med J 1976;1:372-5.

15. Gaby, AR. Nutritional Medicine. Concord, NH: Fritz Perlberg Publishing, 2011.

16. Hollowell JG, Staehling NW, Hannon WH, et al. Iodine nutrition in the United States. Trends and public health implications: iodine excretion data from National Health and Nutrition Examination Surveys I and III (1971-1974 and 1988-1994). J Clin Endocrinol Metab 1998;83:3401-8.

17. Mu L, Derun L, Chengyi Q, et al. Endemic goiter in central China caused by excessive iodine intake. Lancet 1987;2:257-9.

18. Heymann WR. Potassium iodide and the Wolff-Chaikoff effect: Relevance for the dermatologist. J Am Acad Dermatol. 2000 Mar;42:490-2.

19. Pennington JA. A review of iodine toxicity reports. J Am Diet Assoc 1990;90:1571-81.

20. Williams ED, Doniach I, Bjarnason O, et al. Thyroid cancer in an iodide rich area. Cancer 1977;39:215-22.

21. Kim JY, Kim KR. Dietary iodine intake and urinary iodine excretion in patients with thyroid diseases. Yonsei Med J. 2000;41:22-8.

22. Harach HR, Williams ED. Thyroid cancer and thyroiditis in the goitrous region of Salta, Argentina, before and after iodine prophylaxis. Clin Endocrinol (Oxf) 1995;43:701-6.

23. Harach HR, Escalante DA, Onativia A, et al. Thyroid carcinoma and thyroiditis in an endemic goitre region before and after iodine prophylaxis. Acta Endocrinol (Copenh) 1985;108:55-60.

24. Papanastasiou L, Alevizaki M, Piperingos G, et al. The effect of iodine administration on the development of thyroid autoimmunity in patients with nontoxic goiter. Thyroid 2000;10:493-7.

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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.