Centiles for energy costs of tissue deposition in infancy, childhood, and adolescence: calculations based on reanalysis of United Kingdom body composition reference data

Le résumé fourni par la source

BACKGROUND: The WHO recommends that pediatric energy requirements be estimated as the sum of total energy expenditure and the energy content of tissue deposited through growth. WHO growth estimates for children aged 2+ y are based on an assumed 2 kcal/g tissue gained, and do not address age or sex variability in the composition of accreted tissue. We revisited growth costs using objective body composition data. METHODS: We conducted a secondary data analysis of United Kingdom reference data. Using 7 centiles for fat-free mass and fat mass, we calculated fat and protein deposition rates and their energy costs. We generated new centiles for total body energy content from body composition data, where velocities indicate total growth energy costs. Median values were compared with WHO reference values. RESULTS: Compared with WHO values, the median United Kingdom child deposits more energy in infancy and through childhood from 2 y in females. Median protein deposition declines through infancy before rising in adolescence, peaking at 12 y (females) and 14 y (males). Median fat deposition declines through infancy and is relatively constant in both sexes through childhood, although higher centiles differ by sex. United Kingdom children have higher median growth costs than WHO values for males in late infancy and for females at most ages. Older children, measured more recently (2001-2010), had greater adiposity and growth costs than younger children (1987-1996). Individual children showed a degree of trade-off between fat and protein deposition. CONCLUSIONS: We provide new centiles for total energy costs of growth and for fat and protein accretion rates and costs. Growth energy requirements in United Kingdom children, especially females, differ from WHO values, due primarily to greater fat deposition in more recent cohorts. Our approach may be applied to other centile data to improve understanding of variability in growth costs across populations and time periods.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.