title: Energy requirements derived from total energy expenditure and energy deposition during the first 2 y of life.
abstract: BACKGROUND
  Current recommendations for energy intake of children are derived from observed intakes. Deriving energy requirements on the basis of energy expenditure and deposition is scientifically more rational than is using the observational approach and is now possible with data on total energy expenditure (TEE), growth, and body composition.
  
  
  OBJECTIVE
  The objectives of this study were 1) to define energy requirements during the first 2 y of life on the basis of TEE and energy deposition; 2) to test effects of sex, age, and feeding mode on energy requirements; and 3) to determine physical activity.
  
  
  METHODS
  TEE, sleeping metabolic rate, anthropometry, and body composition were measured in 76 infants. TEE was measured with doubly labeled water, sleeping metabolic rate with respiratory calorimetry, and body composition with a multicomponent model.
  
  
  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, respectively. Energy deposition (in MJ/d) decreased significantly over time (P: = 0.001) and was lower in breast-fed than in formula-fed infants (P: = 0.01). Energy requirements were approximately 80% of current recommendations. Energy requirements differed by age (P: = 0.001), feeding group (P: = 0.03), and sex (P: = 0.03). Adjusted for weight or fat-free mass and fat mass, energy requirements still differed by feeding group but not by age or sex. Temperament and motor development did not affect TEE.
  
  
  CONCLUSIONS
  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.
authors: US Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Houston, TX 77030, USA. nbutte@bcm.tmc.edu
authors: N F
authors: NF
authors: Butte
authors: W W
authors: WW
authors: Wong
authors: J M
authors: JM
authors: Hopkinson
authors: C J
authors: CJ
authors: Heinz
authors: N R
authors: NR
authors: Mehta
authors: E O
authors: EO
authors: Smith
mesh_terms: D000886:Anthropometry; D001724:Birth Weight; D001823:Body Composition; D001942:Breast Feeding; D002151:Calorimetry; D002657:Child Development; D002149:Energy Intake; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D007225:Infant Food; D007231:Infant, Newborn; D008297:Male; D009751:Nutritional Requirements; D017678:Sex Distribution; D012890:Sleep