title: Reaching the healthy people goals for reducing childhood obesity: closing the energy gap.
abstract: BACKGROUND
  The federal government has set measurable goals for reducing childhood obesity to 5% by 2010 (Healthy People 2010), and 10% lower than 2005-2008 levels by 2020 (Healthy People 2020). However, population-level estimates of the changes in daily energy balance needed to reach these goals are lacking.
  
  
  OBJECTIVE
  To estimate needed per capita reductions in youths' daily "energy gap" (calories consumed over calories expended) to achieve Healthy People goals by 2020.
  
  
  METHODS
  Analyses were conducted in 2010 to fit multivariate models using National Health and Nutrition Examination Surveys 1971-2008 (N=46,164) to extrapolate past trends in obesity prevalence, weight, and BMI among youth aged 2-19 years. Differences in average daily energy requirements between the extrapolated 2020 levels and Healthy People scenarios were estimated.
  
  
  RESULTS
  During 1971-2008, mean BMI and weight among U.S. youth increased by 0.55 kg/m(2) and by 1.54 kg per decade, respectively. Extrapolating from these trends to 2020, the average weight among youth in 2020 would increase by ∼1.8 kg from 2007-2008 levels. Averting this increase will require an average reduction of 41 kcal/day in youth's daily energy gap. An additional reduction of 120 kcal/day and 23 kcal/day would be needed to reach Healthy People 2010 and Healthy People 2020 goals, respectively. Larger reductions are needed among adolescents and racial/ethnic minority youth.
  
  
  CONCLUSIONS
  Aggressive efforts are needed to reverse the positive energy imbalance underlying the childhood obesity epidemic. The energy-gap metric provides a useful tool for goal setting, intervention planning, and charting progress.
authors.affiliation: Department of Health Policy and Management, Columbia Mailman School of Public Health, New York, New York 10032, USA. ycw2102@columbia.edu
authors.forename: Y Claire
authors.initials: YC
authors.lastname: Wang
authors.forename: C Tracy
authors.initials: CT
authors.lastname: Orleans
authors.forename: Steven L
authors.initials: SL
authors.lastname: Gortmaker
mesh_terms: D000293:Adolescent; D000367:Age Factors; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D004032:Diet / Q000706:statistics & numerical data; D002149:Energy Intake; D015444:Exercise; D005260:Female; D040361:Healthy People Programs / Q000458:organization & administration*; D006801:Humans; D007182:Income; D008297:Male; D009765:Obesity / Q000453:epidemiology* / Q000517:prevention & control*; D044469:Racial Groups; D012737:Sex Factors; D014481:United States