Water turnover in children and young adults
Water homeostasis is essential for life and optimal function and considerable interest surrounds the issue of recommendations for water consumption in healthy individuals. Objective data on water turnover in free-living individuals are limited, however. The aim of the present work was to measure water turnover in children and young adults using isotopically labeled water to provide objective data on magnitude and variability in relation to body weight, fat-free mass and physical activity level. Water turnover was measured by deuterated water dilution in 91 healthy children (40 boys, 51 girls; age 5–14 years) and 109 healthy young adults (80 women, 29 men; age 18–27 years) with a wide range of body mass index (13.3–51.8 kg/m2) and percent body fat (6.1–59.3%). Total energy expenditure (TEE) and resting metabolic rate were measured by the doubly labeled water technique and indirect calorimetry, respectively. Water turnover was 1.77 ± 0.57 (SD), 1.79 ± 0.44, 2.85 ± 0.82, and 3.90 ± 0.81 L/day in girls, boys, women, and men, respectively. Water turnover indexed to body surface area did not differ significantly between girls and women but was higher in men than boys. Water turnover indexed to TEE was 0.8 mL/kcal in girls and boys and 1.0 mL/kcal in women and men. This study provides objective data on water turnover for children and young adults in a temperate climate and shows that anthropometric parameters can account for the variation between girls, boys and women but not between these groups and the more active men.
KeywordsWater turnover Children Young adults Doubly labeled water Deuterium dilution
- Food and Nutrition Board (1989) Recommended Dietary Allowances, 10th edn. National Academy Press. WashingtonGoogle Scholar
- Johansson G, Wikman A, Ahren AM, Hallmans G, Johansson I (2001) Underreporting of energy intake in repeated 24-hour recalls related to gender, age, weight status, day of interview, educational level, reported food intake, smoking habits and area of living. Public Health Nutr 4:919–927CrossRefPubMedGoogle Scholar
- Lohman TG (1986) Applicability of body composition techniques and constants for children and youths. Exerc Sport Sci Rev 14:325–357Google Scholar
- Otten J, Helling J, Meyes L (eds) (2006) Dietary reference intakes, the essential guide to nutrient requirements. National Academy Press, WashingtonGoogle Scholar