Usefulness and Pitfalls in Sodium Intake Estimation: Comparison of Dietary Assessment and Urinary Excretion in Chilean Children and Adults.
High sodium intake has been associated with various noncommunicable disease like hypertension, cardiovascular disease, or stroke. To estimate accurately sodium intake is challenging in clinical practice. We investigate the usefulness and limitations of assessing sodium intake simultaneously by dietary assessment and urinary samples in both children and adults.



We used a cross-sectional study design inviting 298 Chilean subjects (74 children and 222 adults) aged between 9 and 66 years of both genders. Sodium intake by dietary assessment was obtained from Chilean food composition data, based on FAO tables. Sodium and creatinine excretion were measured in 24-hour urine samples, in all participants.



Adequate urinary collection was obtained in 81% of children (59/74) and 61% of adults (135/222). The mean sodium intake by dietary assessment was similar to the sodium excretion in 24 hours (3,121±1,153mg/d vs. 3,114±1,353mg/24h, P = nonsignificant) in children but was significantly lower (3,208±1,284mg/d vs. 4,160±1,651mg/24h, P < 0.001) in adults. In both children and adults, sodium intake correlated with urinary sodium excretion (r = 0.456, P < 0.003 and r = 0.390, P < 0.001, respectively). Secondary analyses also suggested that the dietary assessment was more inaccurate in overweight adult subjects.



Our results showed that average sodium intake was higher than recommended in both children and adults (WHO ≤2,000mg/d). The sodium intake estimated by dietary assessment correlated with urinary excretion in all subjects, but in obese adults was more inaccurate than in children. Future studies to validate the appropriate test to assess sodium intake by age and nutritional status are warranted.
Departamento Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute of Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile;
Carmen
C
Campino
Unidad de Diálisis Peritoneal, Departamento Nefrología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Caroline
C
Hill
Departamento Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Rene
R
Baudrand
División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Alejandro
A
Martínez-Aguayo
División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Marlene
M
Aglony
Departamento Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Carmen A
CA
Carrasco
División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Clarita
C
Ferrada
División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Carolina
C
Loureiro
Departamento Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute of Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile;
Andrea
A
Vecchiola
División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Rodrigo
R
Bancalari
División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Francisca
F
Grob
Departamento Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute of Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile;
Cristian A
CA
Carvajal
Departamento Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute of Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile; Facultad de Ciencia, Universidad San Sebastián, Santiago, Chile.
Carlos F
CF
Lagos
Departamento Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute of Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile;
Carolina
C
Valdivia
Departamento Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute of Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile;
Alejandra
A
Tapia-Castillo
Departamento Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute of Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile;
Cristobal A
CA
Fuentes
División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Carolina
C
Mendoza
División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Hernan
H
Garcia
División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile;
Ricardo
R
Uauy
Departamento Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Institute of Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile; cfardella@med.puc.cl.
Carlos E
CE
Fardella
D000293:Adolescent; D000328:Adult; D000368:Aged; D001835:Body Weight; D002648:Child; D002677:Chile; D003430:Cross-Sectional Studies; D004034:Diet Surveys; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015596:Nutrition Assessment; D012982:Sodium, Dietary / Q000652:urine*; D055815:Young Adult
D012982:Sodium, Dietary
blood pressure; dietary assessment; hypertension; sodium excretion; sodium intake; urine biomarker.