Journal List > Int J Thyroidol > v.8(2) > 1082720

Int J Thyroidol. 2015 Nov;8(2):170-182. Korean.
Published online November 30, 2015.
Copyright © 2015. the Korean Thyroid Association. All rights reserved.
An Iodine Database for Common Korean Foods and the Association between Iodine Intake and Thyroid Disease in Korean Adults
Mi-Rhan Han,1 Dal Lae Ju,2 Young Joo Park,3 Hee-Young Paik,4 and YoonJu Song1
1Major of Food & Nutrition, School of Human Ecology, The Catholic University of Korea, Bucheon, Korea.
2Department of Food Service and Nutrition Care, Seoul National University Hospital, Seoul, Korea.
3Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
4Department of Food and Nutrition, Seoul National University, Seoul, Korea.

Correspondence: YoonJu Song, PhD, Major of Food & Nutrition, School of Human Ecology, The Catholic University of Korea, 43 Jibong-ro, Wonmi-gu, Bucheon 420-743, Korea. Tel: 82-2-2164-4681, Fax: 82-2-2164-6583, Email:
Received April 12, 2015; Revised May 25, 2015; Accepted June 08, 2015.

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.


Background and Objectives

Iodine is essential for thyroid hormone production and the iodine intake of Koreans is high. Few studies have examined the association between iodine intake and thyroid disease in the Korean population due to the lack of an iodine database. Therefore, this study established an iodine database, evaluated iodine intake levels, and explored the association between iodine intake and thyroid disease.

Materials and Methods

We obtained data for 9998 subjects who had both biochemical and dietary data from the 2007-2009 Korea National Health and Nutrition Examination Survey.


An iodine database was established for 667 food items. The median iodine intake in the population was 375.4 µg per day. The iodine contribution by food group was 65.6% from seaweed, 18.0% from salted vegetables, and 4.8% from fish. When subjects were divided into five groups across quintiles of iodine intake per 1000 kcal, excluding extreme subjects who consumed above the upper limit, age, sex, income, education, drinking, and smoking differed across the groups. While the energy and fat intakes decreased, other nutrients increased across the quintile groups. The consumption of seaweeds, fish, eggs, and salted vegetables increased across the quintile groups. After adjusting for all potential confounding variables, the odds ratio for thyroid disease in the highest quintile was 1.63 compared to that in the lowest quintile (p for trend=0.0352).


The iodine intake of the Korean population is high, with high consumption of seaweeds, salted vegetables, and fish positively associated with thyroid disease.

Keywords: Iodine; Intake; Database; Thyroid disease; Korean


Fig. 1
The distribution of iodine intake in the Korean adults population aged 20 or more using the data from 2007-2009 Korea National Health and Nutrition Examination Survey. Box: Q3-Q1 (Interquartile range), Q1: 25th percentile, Q3: 75th percentile
Click for larger image

Fig. 2
The average and range of iodine intake across quintile and extreme group. Quintile group was classified based on the iodine intake per 1000 kcal.
Click for larger image


Table 1
Composition of the table of iodine values for common Korean foods
Click for larger image

Table 2
The contribution of iodine intake according to food groups in total population
Click for larger image

Table 3
Socio-demographic characteristics of study subjects
Click for larger image

Table 4
Nutrient intake of study subjects
Click for larger image

Table 5
Food group intakes across quintile of iodine intake including extreme group
Click for larger image

Table 6
The odds ratio for thyroid disease across the quintile of iodine intakes
Click for larger image


This study was supported by the Research Fund, 2014 of The Catholic University of Korea.

1. Kim JH, Park SJ, Kim SE, Lee KH, Cho IK, Jang SI, et al. Prevalence of thyroid nodules detected by ultrasonography in adult men attending health check-ups. J Korean Endocr Soc 2007;22(2):112–117.
2. Suk JH, Kim TY, Kim MK, Kim WB, Kim HK, Jeon SH, et al. Prevalence of ultrasonographically-detected thyroid nodules in adults without previous history of thyroid disease. J Korean Endocr Soc 2006;21(5):389–393.
3. Yim CH, Oh HJ, Chung HY, Han KO, Jang HC, Yoon HK, et al. Prevalence of thyroid nodules detected by ultrasonography in womens attending health check-ups. J Korean Soc Endocrinol 2002;17(2):183–188.
4. Kim SY, Hyun MK. In: A evidence-based study on the effectiveness of thyroid cancer screening test. Seoul, Korea: National Evidence-based Healthcare Collaborating Agency (NECA); 2012.
5. Choi HS, Park YJ, Kim HK, Choi SH, Lim S, Park DJ, et al. Prevalence of subclinical hypothyroidism in two population based-cohort: Ansung and KLoSHA cohort in Korea. J Korean Thyroid Assoc 2010;3(1):32–40.
6. Jung KW, Won YJ, Kong HJ, Oh CM, Cho H, Lee DH, et al. Cancer statistics in Korea: incidence, mortality, survival, and prevalence in 2012. Cancer Res Treat 2015;47(2):127–141.
7. Laurberg P, Cerqueira C, Ovesen L, Rasmussen LB, Perrild H, Andersen S, et al. Iodine intake as a determinant of thyroid disorders in populations. Best Pract Res Clin Endocrinol Metab 2010;24(1):13–27.
8. Lee HS, Min H. Iodine intake and tolerable upper intake level of iodine for Koreans. Korean J Nutr 2011;44(1):82–91.
9. Teng W, Shan Z, Teng X, Guan H, Li Y, Teng D, et al. Effect of iodine intake on thyroid diseases in China. N Engl J Med 2006;354(26):2783–2793.
10. Vejbjerg P, Knudsen N, Perrild H, Laurberg P, Carle A, Pedersen IB, et al. Lower prevalence of mild hyperthyroidism related to a higher iodine intake in the population: prospective study of a mandatory iodization programme. Clin Endocrinol (Oxf) 2009;71(3):440–445.
11. Konno N, Makita H, Yuri K, Iizuka N, Kawasaki K. Association between dietary iodine intake and prevalence of subclinical hypothyroidism in the coastal regions of Japan. J Clin Endocrinol Metab 1994;78(2):393–397.
12. Kim JY, Moon SJ, Kim KR, Sohn CY, Oh JJ. Dietary iodine intake and urinary iodine excretion in normal Korean adults. Yonsei Med J 1998;39(4):355–362.
13. Kim JY, Kim KR. Dietary iodine intake and urinary iodine excretion in patients with thyroid diseases. Yonsei Med J 2000;41(1):22–28.
14. Imaeda N, Kuriki K, Fujiwara N, Goto C, Tokudome Y, Tokudome S. Usual dietary intakes of selected trace elements (Zn, Cu, Mn, I, Se, Cr, and Mo) and biotin revealed by a survey of four-season 7-consecutive day weighed dietary records in middle-aged Japanese dietitians. J Nutr Sci Vitaminol (Tokyo) 2013;59(4):281–288.
15. Kang TS. In: Monitoring of iodine in foods for estimation of dietary intake. Naterional Institute of Food and Drug Safety Evaluation; 2012.
16. Lee JY. In: Iodine analysis method establishment and content monitoring of food. Global Health Care, Korea National Institute of Food and Drug Safety; 2006.
17. Kim BH. In: Development of nutrient database - 3. Mineral composition of foods -. Korea Health Industry Development Institute; 2003.
18. Moon SJ, Kim JY, Chung YJ, Chung YS. The iodine content in common Korean foods. Korean J Nutr 1998;31(2):206–212.
19. National Rural Living Science Institute. Food composition table. Rural Development Administration; 2006.
20. Chang NS, Cho YW, Kim WJ. Iodin intake and excretion of the patients with thyroid disease. Korean J Nutr 1994;27(10):1037–1047.
21. The Korean Nutrition Society. Food values. The Korean Nutrition Society; 2009.
22. Kim EH, Choi TI, Park YK. Dietary iodine intake and the association with subclinical thyroid dysfunction in male workers. Korean J Nutr 2012;45(3):218–228.
23. Ristic-Medic D, Dullemeijer C, Tepsic J, Petrovic-Oggiano G, Popovic T, Arsic A, et al. Systematic review using meta-analyses to estimate dose-response relationships between iodine intake and biomarkers of iodine status in different population groups. Nutr Rev 2014;72(3):143–161.
24. Luo Y, Kawashima A, Ishido Y, Yoshihara A, Oda K, Hiroi N, et al. Iodine excess as an environmental risk factor for autoimmune thyroid disease. Int J Mol Sci 2014;15(7):12895–12912.
25. Michikawa T, Inoue M, Shimazu T, Sawada N, Iwasaki M, Sasazuki S, et al. Seaweed consumption and the risk of thyroid cancer in women: the Japan Public Health Center-based Prospective Study. Eur J Cancer Prev 2012;21(3):254–260.
26. Matsubayashi S, Mukuta T, Watanabe H, Fuchigami H, Taniguchi J, Chinen M, et al. Iodine-induced hypothyroidism as a result of excessive intake of confectionery made with tangle weed, Kombu, used as a low calorie food during a bulimic period in a patient with anorexia nervosa. Eat Weight Disord 1998;3(1):50–52.
27. Cho NH, Choi HS, Kim KW, Kim HL, Lee SY, Choi SH, et al. Interaction between cigarette smoking and iodine intake and their impact on thyroid function. Clin Endocrinol (Oxf) 2010;73(2):264–270.