title: Causes of increased energy intake among children in the U.S., 1977-2010.
abstract: BACKGROUND
  Changes in total energy intake have been reported among children and adolescents, but the extent to which the components of total energy-energy density; portion size; and the number of eating/drinking occasions (EO)-drive these changes is unknown.
  
  
  OBJECTIVE
  The objective of the current study was to examine the relative contribution to changes in daily total energy.
  
  
  METHODS
  Using cross-sectional nationally representative data from the Nationwide Food Consumption Survey (1977-1978); the Continuing Survey of Food Intake of Individuals (1989-1991); and the National Health and Nutrition Examination Surveys (1994-1998 and 2005-2010) for children and adolescents (aged 2-18 years), changes in total energy (kcal/day) were mathematically decomposed to determine the relative contributions of its three component parts: portion size (g/EO); energy density (kcal/g/EO); and eating/drinking occasions (n). Analyses were completed in 2012.
  
  
  RESULTS
  Over the full period, there was an increase in total energy intake (+108 kcal/day) and the number of daily eating/drinking occasions (+1.2). The average portion size per eating/drinking occasion increased between 1977-1978 and 1989-1991, and then dropped by about 85 g/EO between 1989-1991 and 2005-2010. The average energy density per eating/drinking occasion has fluctuated over time, reaching its highest level in 2005-2010 (1.24 kcal/g/EO). The decomposition results show that between 1977-1978 and 2005-2010, changes in the number of eating/drinking occasions per day and portion size per eating occasion were the largest contributors to annualized changes in daily total energy (+19 and -13 kcal/day/year, respectively). Variations in trends were observed for race/ethnicity and parental education subgroups.
  
  
  CONCLUSIONS
  These findings highlight potentially important intervention targets for reducing energy imbalances in U.S. youth.
authors: Carolina Population Center, Chapel Hill, North Carolina, USA.
authors: Kiyah J
authors: KJ
authors: Duffey
authors: Barry M
authors: BM
authors: Popkin
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004327:Drinking Behavior; D004522:Educational Status; D002149:Energy Intake / Q000208:ethnology; D005247:Feeding Behavior / Q000208:ethnology; D005260:Female; D006801:Humans; D008297:Male; D009749:Nutrition Surveys; D010290:Parents; D014481:United States