|Smith, E O'brian|
Submitted to: American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/30/2000
Publication Date: N/A
Citation: N/A Interpretive Summary: Currently, the recommended energy intakes of children from birth to 10 years of age are based on observed intakes. Requirements for individuals over age 10 years are based on energy expenditure, a more logical method of determining how much energy intake is necessary. However, there have not been total energy expenditure data available on babies and children from birth to age 2 years. We performed this study in order to get such data. W performed repeated measurements including total energy expenditure, sleeping metabolic rate, body composition, temperament and motor development on both breast-fed and formula-fed boys and girls from birth to 2 years of age. The total energy expenditure and energy deposition data of the 76 children we studied provide strong evidence that the current recommendations for energy intake during the first 2 years of life should be revised. Our findings suggest they should be lower. This is quite significant with regard to our knowledge of how much babies and toddlers should be eating in order to support proper growth and development.
Technical Abstract: Current recommendations for energy intake of children are derived from observed intakes. Derivation of energy requirements based on energy expenditure and energy deposition is scientifically more rational and now possible with data on total energy expenditure (TEE), physical activity levels (PAL), growth and body composition. Objectives: 1) To define energy requirements during the first two years of life based on TEE and energy deposition; 2) to test the effects of sex, age, body size and composition, feeding mode, motor development and temperament on energy requirements; and 3) to determine levels of physical activity. Design: TEE, sleeping metabolic rate (SMR), anthropometry, body composition, motor development and temperament were measured in 76 infants at 3, 6, 9, 12, 18 and 24 mo of age. TEE was measured by the doubly labeled water method, SMR by respiratory calorimetry, body composition by a multicomponent model, motor development by Bayley Scales, and temperament by Carey Questionnaires. Results: Total energy requirements were 2.23, 2.59, 2.97, 3.38, 3.72 and 4.15 MJ/d at 3, 6, 9, 12, 18, and 24 mo of age, respectively. Energy deposition (MJ/d) decreased significantly over time (P=0.001) and tended to be lower in BF than FF infants (P=0.01). Energy requirements were ~80% of current recommendations. Energy requirements differed by age (P=0.001), feeding mode (P=0.03) and sex (P=0.03). Adjusted for weight or fat free mass and fat mass, energy requirements still differed by feeding mode, but not by age or sex. Temperament and motor development did not affect TEE. Conclusion: The TEE and energy deposition data of these healthy, thriving children provide strong evidence that current recommendations for energy intake in the first 2 y of life should be revised.