Lebanese children are iodine deficient and urinary sodium and fluoride excretion are weak positive predictors of urinary iodine
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To assess iodine and fluoride status among Lebanese children.
A nationally representative cross-sectional study of 6- to 10-year-old schoolchildren was conducted using multistage cluster sampling. Spot urine samples were collected from 1403 children, and urinary iodine, fluoride, creatinine and sodium levels were measured. Salt samples from markets (n = 30) were tested for iodine concentration by titration.
Median urinary iodine concentration was 66.0 µg/l, indicating mild deficiency, and almost 75 % of Lebanese children had a urinary iodine concentration (UIC) <100 µg/l. UIC was higher among children from private schools and in areas of higher socioeconomic status. Most salt samples were fortified at levels far below the legislated requirement, and 56 % of samples contained less than 15 ppm iodine. Fluoride-to-creatinine ratio (F/Cr) was 0.250 (0.159–0.448) mg/g. There were weak positive correlations between UIC and urinary sodium (r 2 = 0.039, P value <0.001) and UIC and urinary fluoride (r 2 = 0.009, P value <0.001).
Lebanese elementary school children are iodine deficient due to inadequately iodized salt. The weak correlation between UIC and urinary sodium suggests most dietary iodine does not come from iodized salt. The poor correlation between UIC and urinary fluoride suggests that fluoride intake is not affecting iodine metabolism. Efforts are needed in Lebanon to improve industry compliance with salt fortification through improved monitoring and enforcement of legislation.
KeywordsUrinary iodine excretion Urinary fluoride Iodine/creatinine ratio Fluoride/creatinine ratio Sodium/creatinine ratio Lebanon
This work was funded by the University Research Board (URB) and Iodine Global Network (IGN), and both institutions had no direct or indirect involvements in this project.
Compliance with ethical standards
Integrity of research and reporting
The study protocol was approved by the Institutional Review Board of the American University of Beirut.
Conflict of interest
The authors declare that they have no conflict of interest.
All subjects gave their informed consent prior to their inclusion in the study.
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