title: Sodium and potassium urinary excretion and dietary intake: a cross-sectional analysis in adolescents.
abstract: BACKGROUND
  Hypertension is the leading cause for heart disease and stroke, for mortality and morbidity worldwide, and a high sodium-to-potassium intake ratio is considered a stronger risk factor for hypertension than sodium alone.
  
  
  OBJECTIVE
  This study aims to evaluate sodium and potassium urinary excretion, and assess the food sources of these nutrients in a sample of Portuguese adolescents.
  
  
  METHODS
  A cross-sectional study with a sample of 250 Portuguese adolescents. Sodium and potassium excretion were measured by one 24-h urinary collection, and the coefficient of creatinine was used to validate completeness of urine collections. Dietary sources of sodium and potassium were assessed using a 24-h dietary recall.
  
  
  RESULTS
  Valid urine collections were provided by 200 adolescents (118 girls) with a median age of 14.0 in both sexes (p=0.295). Regarding sodium, the mean urinary excretion was 3,725 mg/day in boys and 3,062 mg/day in girls (p<0.01), and 9.8% of boys and 22% of girls met the World Health Organization (WHO) recommendations for sodium intake. Concerning potassium, the mean urinary excretion was 2,237 mg/day in boys and 1,904 mg/day in girls (p<0.01), and 6.1% of boys and 1.7% of girls met the WHO recommendations for potassium intake. Major dietary sources for sodium intake were cereal and cereal products (41%), meat products (16%), and milk and milk products (11%); and for potassium intake, main sources were milk and milk products (21%), meat products (17%), and vegetables (15%).
  
  
  CONCLUSIONS
  Adolescents had a high-sodium and low-potassium diet, well above the WHO recommendations. Health promotion interventions are needed in order to decrease sodium and increase potassium intake.
authors.affiliation: Faculty of Nutrition and Food Sciences, University of Porto, Porto, Portugal; carlagoncalves.pt@gmail.com.
authors.forename: Carla
authors.initials: C
authors.lastname: Gonçalves
authors.affiliation: Research Centre in Physical Activity, Health and Leisure, Faculty of Sport, University of Porto, Porto, Portugal.
authors.forename: Sandra
authors.initials: S
authors.lastname: Abreu
authors.affiliation: Faculty of Nutrition and Food Sciences, University of Porto, Porto, Portugal.|Institute of Public Health, University of Porto (ISPUP), EPIUnit-Epidemiology Research Unit, Porto, Portugal.
authors.forename: Patrícia
authors.initials: P
authors.lastname: Padrão
authors.affiliation: Faculty of Nutrition and Food Sciences, University of Porto, Porto, Portugal.|LAQV/REQUIMTE, University of Porto, Porto, Portugal.
authors.forename: Olívia
authors.initials: O
authors.lastname: Pinho
authors.affiliation: Faculty of Nutrition and Food Sciences, University of Porto, Porto, Portugal.|Directorate General of Health, Lisbon, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Graça
authors.affiliation: Division of Noncommunicable Diseases and Health through the Life-Course, World Health Organization Regional Office for Europe, UN City, Denmark.
authors.forename: João
authors.initials: J
authors.lastname: Breda
authors.affiliation: Research Centre in Physical Activity, Health and Leisure, Faculty of Sport, University of Porto, Porto, Portugal.|Maia University Institute, Maia, Portugal.|Early Start Research Institute, School of Education, Faculty of Social Sciences, University of Wollongong, Australia.
authors.forename: Rute
authors.initials: R
authors.lastname: Santos
authors.affiliation: Faculty of Nutrition and Food Sciences, University of Porto, Porto, Portugal.|Research Centre in Physical Activity, Health and Leisure, Faculty of Sport, University of Porto, Porto, Portugal.|Institute of Public Health, University of Porto (ISPUP), EPIUnit-Epidemiology Research Unit, Porto, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Moreira
keywords: adolescents; intake; salt; urinary potassium; urinary sodium