Abstract
Purpose
To estimate total sodium (Na) and potassium (K) intake using non-fasting morning urine specimens among Lebanese elementary (6–10 year old) schoolchildren.
Method
A national cross-sectional study was conducted. A multistage cluster sampling procedure was used to select a representative sample of 1403 healthy children from the eight districts of Lebanon. Age, anthropometric measurements, and urine samples were collected and analyzed for Na, K, and creatinine (Cr).
Results
The ratios of Na and K to Cr were 23.93 ± 15.54 mM/mM (4.86 ± 3.16 mg/mg) and 11.48 ± 5.82 mM/mM (3.97 ± 2.01 mg/mg), respectively, and showed differences (P value <0.001) between age groups. No differences were found between boys and girls in all the measured Na and K parameters. The estimated mean Na intake was 96.57 ± 61.67 mM/day (2.220 ± 1.418 g/day or 5.69 ± 3.64 g NaCl/day) and exceeded the upper limit of intake in half the children. Estimated K intake was 46.6 ± 23.02 mM/day (1.822 ± 0.900 g/day), and almost all children failed to meet the recommended daily K intake. The high Na/K ratio (2.361 ± 1.67 mM/mM or 1.39 ± 0.98 mg/mg) resulted from a combination of high Na and low K intake but was mostly affected by K intake.
Conclusions
About 50 % of children exceeded the recommended daily upper intake for Na, while the majority was below K adequate intake. This unfavorable Na/K ratio is indicative of potentially negative health effects at later stages in life. Interventions aimed at reducing salt intake and increasing consumption of fruits and vegetables are warranted.
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This work was funded by the University Research Board (URB) which had no direct or indirect involvements in this project.
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All subjects gave their informed consent prior to their inclusion in the study.
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The study protocol was approved by the Institutional Review Board of the American University of Beirut.
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Carla El Mallah and Karina Merhi have contributed equally to the work, and the first listed authors made the greatest contribution to the paper.
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El Mallah, C., Merhi, K., Ghattas, H. et al. Elevated urinary Na/K ratio among Lebanese elementary school children is attributable to low K intake. Eur J Nutr 56, 1149–1156 (2017). https://doi.org/10.1007/s00394-016-1164-6
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DOI: https://doi.org/10.1007/s00394-016-1164-6