Endocrinol Metab.  2017 Sep;32(3):370-374. 10.3803/EnM.2017.32.3.370.

Excessive Iodine Status among School-Age Children in Korea: A First Report

• Choi YS
• Ock S
• Kwon S
• Jung SB
• Seok KH
• Kim YJ
• Kim BK
• Jeong JY

• KMID: 2389818
• DOI: http://doi.org/10.3803/EnM.2017.32.3.370

Abstract

BACKGROUND
Korea is considered an iodine sufficient country, and several studies have been conducted regarding iodine status in healthy Korean adults, pregnant women, and preschool children. However, data on iodine status in Korean school-age children are lacking. Therefore, the iodine nutrition status of Korean school-age children was investigated by measuring urine iodine concentration (UIC).
METHODS
This cross-sectional study conducted between April and September 2016 comprised 373 school-age children. UIC was determined using a modified microplate method employing ammonium persulfate digestion followed by Sandell-Kolthoff reaction.
RESULTS
The median UIC was 458.2 µg/L. Excessive iodine intake (>300 µg/L) was found in 286 children (76.7%), with extremely high values exceeding 1,000 µg/L in 19.6% of subjects. Insufficient iodine intake (<100 µg/L) was observed in eight children (2.1%). UIC values were not significantly different between sexes.
CONCLUSION
Korean school-age children showed excessive iodine intake. Therefore, education regarding adequate iodine intake in school-age children is needed.

Keyword

Urine; Iodine; Schools; Korea

MeSH Terms

Adult
Ammonium Compounds
Child*
Child, Preschool
Cross-Sectional Studies
Digestion
Education
Female
Humans
Iodine*
Korea*
Methods
Nutritional Status
Pregnant Women
Iodine

Figure

• 

  Fig. 1 Distribution of urine iodine concentration in school-aged children from Busan, Korea.

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