24-h urinary sodium to potassium ratio and its association with obesity in children and adolescents
There are epidemiologic studies indicating a positive correlation between high sodium and low potassium intake and body mass index. Therefore, this study was conducted in a cross-sectional sample of Iranian children and adolescents to evaluate the link between 24-h urinary Na:K ratio and risk of obesity.
In this cross-sectional study, 374 participants aged 11–18 years were included. One 24-h urine sample was collected by each participant to estimate Na:K ratio. Anthropometric measurements were carried out and overweight/obesity was defined as a BMI ≥ 85th percentile and abdominal obesity as a waist:height ratio (WHtR) of more than 0.5.
As expected, 24-h urinary Na:K ratio showed significant associations with risk of overweight/obesity. Risk of adiposity assessed by WC and PBF was significantly associated with Na:K ratio after adjusting for SSBs consumption and calorie intake. Urinary Na:K ratio showed significant association with risk of adiposity assessed by WC only in girls in the highest tertile group with OR of 2.71 (95% CI 1.14–6.43), only after the addition of calorie intake. Adiposity assessed by PBF was only associated with Na:K ratio among boys with OR of 4.47 (95% CI 1.44–9.87) and 3.87 (95% CI 1.20–8.48), after adjusting for SSBs consumption and calorie intake, respectively.
Our findings suggest that reducing Na and increasing K intake could be used as a useful approach to lower the risk of obesity and associated burden of disease in Iran. However, more studies are warranted.
KeywordsSodium Potassium 24-h urine Overweight Obesity Children Adolescents Iran
This study was supported by Isfahan University of Medical Sciences and Isfahan Cardiovascular Research Institute. The authors would like to thank all the schools and students/parents who agreed to participate in this study.
Compliance with ethical standards
Conflict of interest
The authors declare no conflict of interests.
- 1.Djalalinia S, Kelishadi R, Qorbani M, Peykari N, Kasaeian A, Nasli-Esfahani E, Naderimagham S, Larijani B, Farzadfar F (2016) A systematic review on the prevalence of overweight and obesity, in iranian children and adolescents. Iran J Pediatr 26(3):e2599. https://doi.org/10.5812/ijp.2599 Google Scholar
- 3.Delavari A, Forouzanfar MH, Alikhani S, Sharifian A, Kelishadi R (2009) First nationwide study of the prevalence of the metabolic syndrome and optimal cutoff points of waist circumference in the Middle East: the national survey of risk factors for noncommunicable diseases of Iran. Diabetes Care 32(6):1092–1097. https://doi.org/10.2337/dc08-1800 CrossRefGoogle Scholar
- 4.Haghdoost AA, Rezazadeh-Kermani M, Sadghirad B, Baradaran HR (2009) Prevalence of type 2 diabetes in the Islamic Republic of Iran: systematic review and meta-analysis. East Mediterr Health J 15(3):591–599Google Scholar
- 9.Kelishadi R, Gheisari A, Zare N, Farajian S, Shariatinejad K (2013) Salt intake and the association with blood pressure in young Iranian children: first report from the middle East and north Africa. Int J Prev Med 4(4):475–483Google Scholar
- 12.Cappuccio FP, Kalaitzidis R, Duneclift S, Eastwood JB (2000) Unravelling the links between calcium excretion, salt intake, hypertension, kidney stones and bone metabolism. J Nephrol 13(3):169–177Google Scholar
- 20.O’Donnell MJ, Yusuf S, Mente A, Gao P, Mann JF, Teo K, McQueen M, Sleight P, Sharma AM, Dans A (2011) Urinary sodium and potassium excretion and risk of cardiovascular events. Jama 306(20):2229–2238Google Scholar
- 26.Kelishadi R, Majdzadeh R, Motlagh M-E, Heshmat R, Aminaee T, Ardalan G, Esmaillzadeh A, Azadbakht L, Poursafa P, Movahedian M (2012) Development and evaluation of a questionnaire for assessment of determinants of weight disorders among children and adolescents: The Caspian-IV study. Int J Prev Med 3(10):699Google Scholar
- 27.Ghaffarpour M, Houshiar-Rad A, Kianfar H (1999) The manual for household measures, cooking yields factors and edible portion of foods. Tehran: Nashre Olume Keshavarzy 7:213Google Scholar
- 28.Faghihimani Z, Nourian M, Nikkar AH, Farajzadegan Z, Khavariyan N, Ghatrehsamani S, Poursafa P, Kelishadi R (2010) Validation of the child and adolescent international physical activity questionnaires in Iranian children and adolescents. ARYA Atheroscler 5 (4)Google Scholar
- 29.Fahimi S, Pharoah P (2012) Reducing salt intake in Iran: priorities and challenges. Arch Iran Med 15(2):110–112. http://www.sid.ir/En/Journal/ViewPaper.aspx?ID=243264 Google Scholar