title: Prevalence of obesity and trends in body mass index among US children and adolescents, 1999-2010.
abstract: BACKGROUND
  The prevalence of childhood obesity increased in the 1980s and 1990s but there were no significant changes in prevalence between 1999-2000 and 2007-2008 in the United States.
  
  
  OBJECTIVE
  To present the most recent estimates of obesity prevalence in US children and adolescents for 2009-2010 and to investigate trends in obesity prevalence and body mass index (BMI) among children and adolescents between 1999-2000 and 2009-2010.
  
  
  METHODS
  Cross-sectional analyses of a representative sample (N = 4111) of the US child and adolescent population (birth through 19 years of age) with measured heights and weights from the National Health and Nutrition Examination Survey 2009-2010.
  
  
  METHODS
  Prevalence of high weight-for-recumbent length (≥95th percentile on the growth charts) among infants and toddlers from birth to 2 years of age and obesity (BMI ≥95th percentile of the BMI-for-age growth charts) among children and adolescents aged 2 through 19 years. Analyses of trends in obesity by sex and race/ethnicity, and analyses of trends in BMI within sex-specific age groups for 6 survey periods (1999-2000, 2001-2002, 2003-2004, 2005-2006, 2007-2008, and 2009-2010) over 12 years.
  
  
  RESULTS
  In 2009-2010, 9.7% (95% CI, 7.6%-12.3%) of infants and toddlers had a high weight-for-recumbent length and 16.9% (95% CI, 15.4%-18.4%) of children and adolescents from 2 through 19 years of age were obese. There was no difference in obesity prevalence among males (P = .62) or females (P = .65) between 2007-2008 and 2009-2010. However, trend analyses over a 12-year period indicated a significant increase in obesity prevalence between 1999-2000 and 2009-2010 in males aged 2 through 19 years (odds ratio, 1.05; 95% CI, 1.01-1.10) but not in females (odds ratio, 1.02; 95% CI, 0.98-1.07) per 2-year survey cycle. There was a significant increase in BMI among adolescent males aged 12 through 19 years (P = .04) but not among any other age group or among females.
  
  
  CONCLUSIONS
  In 2009-2010, the prevalence of obesity in children and adolescents was 16.9%; this was not changed compared with 2007-2008.
authors.affiliation: National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Maryland 20782, USA. cogden@cdc.gov
authors.forename: Cynthia L
authors.initials: CL
authors.lastname: Ogden
authors.forename: Margaret D
authors.initials: MD
authors.lastname: Carroll
authors.forename: Brian K
authors.initials: BK
authors.lastname: Kit
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Flegal
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009749:Nutrition Surveys; D009765:Obesity / Q000453:epidemiology*; D015995:Prevalence; D014481:United States / Q000453:epidemiology; D055815:Young Adult