Urinary hydration biomarkers and dietary intake in children.

INTRODUCTION The importance of hydration is undoubtable but reliable data on hydration status and its relation with diet is lacking. OBJECTIVES We aimed to evaluate the hydration status and its relation to beverages and food intake in children. METHODS A sample of 172 (50% male), 7-11 year-old children was included in this survey. Participants completed a 24 h urine collection; a 24 hours food recall corresponding to the day of urine collection was applied, weight and height were measured and parents/caregivers fi lled a lifestyle and socio-demographic questionnaire. The free water reserve was used to assess the hydration status. The intakes of food and beverages were compared according to hydration status using the t-test, Mann-Whitney test or unconditional regression models as appropriate. RESULTS More than half of the participants were classifi ed as hypohydrated or at risk of hypohydration (57% in girls and 58% in boys). Compared to hypohydrated children, a signifi cant higher consumption of water (276.2 ± 208.4 vs 188.2 ± 187.4 g/day) and fruit juices (77.6 ± 139.4 vs 14.4 ± 57.2 g/day) was reported by euhydrated boys and girls, respectively. Lower consumers of water and fruit juices showed a higher risk of hypohydration (OR = 2.16, 95% CI: 1.02-4.58, p = 0.045), adjusting for confounders. CONCLUSIONS Most of the children included in this analysis were classifi ed as at risk of hypohydration and those with higher water and fruit juices consumption showed a better hydration status.