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Childhood Obesity Facts

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The percentage of children with obesity in the United States has more than tripled since the 1970s.1 Today, about one in five school-aged children (ages 6–19) has obesity.2

Obesity is defined as having excess body fat.3 Overweight is defined as having excess body weight for a particular height from fat, muscle, bone, water, or a combination of these factors.3 Body mass index, or BMI, is a widely used screening tool for measuring both overweight and obesity. BMI percentile is preferred for measuring children and young adults (ages 2–20) because it takes into account that they are still growing, and growing at different rates depending on their age and sex. Health professionals use growth charts to see whether a child’s weight falls into a healthy range for the child’s height, age, and sex.

  • Children with a BMI at or above the 85th percentile and less than the 95th percentile are considered overweight.
  • Children at or above the 95th percentile have obesity.

For more information about how BMI is measured in children: About Child & Teen BMI

For more information about BMI measurement in school settings: Body Mass Index (BMI) Measurement in Schools

Childhood Obesity and Child Wellbeing

Childhood obesity has immediate and long-term impacts on physical, social, and emotional health. For example:

  • Children with obesity are at higher risk for having other chronic health conditions and diseases that impact physical health, such as asthma, sleep apnea, bone and joint problems, type 2 diabetes, and risk factors for heart disease.4, 5, 15-17
  • Children with obesity are bullied and teased more than their normal weight peers,18 and are more likely to suffer from social isolation, depression, and lower self-esteem.19
  • In the long term, childhood obesity also is associated with having obesity as an adult,23  which is linked to serious conditions and diseases such as heart disease, type 2 diabetes, metabolic syndrome, and several types of cancer.24–25

Energy Balance and Causes of Obesity

Many factors contribute to childhood obesity, including4-6

  • Genetics
  • Metabolism—how your body changes food and oxygen into energy it can use
  • Eating and physical activity behaviors
  • Environmental factors
  • Social and individual psychology

Over time, consuming more energy from foods and beverages than the body uses for healthy functioning, growth, and physical activity, leads to extra weight gain.7, 8 Energy imbalance is a key factor9 behind the high rates of obesity seen in the United States and globally.7, 10–11

The dietary and physical activity behaviors of children and adolescents are influenced by many sectors of society, including families, communities, schools, child care settings, medical care providers, faith-based institutions, government agencies, the media, and the food and beverage industries and entertainment industries.4, 12, 13

Changes in the environments where children spend their time—like homes, schools, and community settings—can help children achieve and maintain a healthy weight by making it easier to eat nutritious foods, get at least 60 minutes of physical activity daily, watch less television, and eat fewer foods and beverages high in added sugars or solid fats.4, 14

Supporting Students With Obesity

Some data show that children with obesity miss more days of school compared to students with normal weights.22  Missed days of school, whether due to illness or to avoid weight-based bullying,23 can make it hard to keep up academically. Many experts believe schools are a key setting for efforts to prevent childhood obesity.4, 5, 24, 25 Looking across multiple studies, teams of scientists have found that a comprehensive school-based approach is effective at preventing obesity.26, 27

This kind of comprehensive approach supports school nutrition and physical activity environments and makes connections beyond the school day by involving parents and caregivers, as well as other community members. These kinds of changes in the school environment can support the health and well-being of all students—regardless of their weight. Most of this research includes elementary and middle school-aged children; scientists know less about the effectiveness of school-based approaches for preventing obesity among teenagers.26, 27

References (expand to view)

  1. Fryar CD, Carroll MD, Ogden CL, Prevalence of overweight and obesity among children and adolescents: United States, 1963-1965 through 2011-2012. Atlanta, GA: National Center for Health Statistics, 2014.
  2. Ogden CL, Carroll MD, Lawman HG, Fryar CD, Kruszon-Moran D, Kit BK, Flegal KM, Trends in Obesity Prevalence Among Children and Adolescents in the United States, 1988-1994 Through 2013-2014. JAMA, 2016. 315(21): p. 2292-2299.
  3. National Heart Lung and Blood Institute. Aim for a Healthy Weight. [cited 2016 August 24]; Available from:
  4. Institute of Medicine, Accelerating progress in obesity prevention: solving the weight of the nation. 2012, Washington, DC: National Academies Press.
  5. US Department of Health and Human Services. The Surgeon General’s Vision for a Healthy and Fit Nation. Rockville, MD: US Dept., Health and Human Services; 2010.
  6. Finegood DT, Merth TDN, Rutter H, Implications of the Foresight Obesity System Map for Solutions to Childhood Obesity. Obesity, 2010. 18(S1): p. S13-S16.
  7. Hill JO, Wyatt HR, Peters JC., Energy balance and obesity. Circulation, 2012. 126(1): p. 126-132.
  8. U.S. Department of Agriculture and U.S. Department of Health and Human Services, Dietary Guidelines for Americans, 2015-2020. 2015, U.S. Government Printing Office: Washington, DC.
  9. Vandenbroeck P, Goossens J, and Clemens M, Foresight, Foresight, tackling obesities: future choices–building the obesity system map. London: Government Office for Science, 2007.
  10. Spiegelman BM, Flier JS, Obesity and the Regulation of Energy Balance. Cell, 2001. 104(4): p. 531-543.
  11. Swinburn BA, Sacks G, Hall KD, McPherson K, Finegood DT, Moodie ML, Gortmaker SL, The global obesity pandemic: shaped by global drivers and local environments. The Lancet, 2011. 378(9793): p. 804-814.
  12. Story M, Kaphingst KM, Robinson-O’Brien R, Glanz K et al., Creating healthy food and eating environments: policy and environmental approaches. Annu. Rev. Public Health, 2008. 29: p. 253-272.
  13. Sallis JF, Prochaska JJ, and Taylor WC, A review of correlates of physical activity of children and adolescents. Medicine and science in sports and exercise, 2000. 32(5): p. 963-975.
  14. Han JC, Lawlor DA, Kimm SY, Childhood obesity. The Lancet, 2010. 375(9727): p. 1737-1748.
  15. Must A, Hollander SA, Economos CD, Childhood obesity: a growing public health concern. Expert Review of Endocrinology & Metabolism, 2006. 1(2): p. 233-254.
  16. Freedman DS, Dietz WH, Srinivasan SR, Berenson GS, Cardiovascular risk factors and excess adiposity among overweight children and adolescents: the Bogalusa Heart Study. The Journal of pediatrics, 2007. 150(1): p. 12-17. e2.
  17. May AL, Kuklina EV, Yoon PW, Prevalence of Cardiovascular Disease Risk Factors Among US Adolescents, 1999−2008. Pediatrics, 2012. 129(6): p. 1035-1041.
  18. van Geel M, Vedder P, Tanilon J, Are overweight and obese youths more often bullied by their peers? A meta-analysis on the correlation between weight status and bullying. Int J Obes (Lond), 2014. 38(10): p. 1263-7.
  19. Griffiths LI, Parsons TJ, Hill AJ, Self-esteem and quality of life in obese children and adolescents: A systematic review. International Journal of Pediatric Obesity, 2010. 5(4): p. 282-304.
  20. Singh AS, Mulder C, Twisk JWR, Van Mechelen V, Chinapaw MJM,  Tracking of childhood overweight into adulthood: a systematic review of the literature. Obesity reviews, 2008. 9(5): p. 474-488.
  21. Biro FM, Wien M, Childhood obesity and adult morbidities. The American journal of clinical nutrition, 2010. 91(5): p. 1499S-1505S.
  22. Geier AB, Foster GD, Womble LG, McLaughlin J, Borradaile KE, Nachmani J, Sherman S, Kumanyika S, Shults J, The relationship between relative weight and school attendance among elementary schoolchildren. Obesity, 2007. 15(8): p. 2157-2161.
  23. Puhl RM, Luedicke J, Weight-based victimization among adolescents in the school setting: Emotional reactions and coping behaviors. Journal of youth and adolescence, 2012. 41(1): p. 27-40.
  24. White House Task Force on Childhood Obesity, Solving the problem of childhood obesity within a generation. White House Task Force on Childhood Obesity Report to the President. 2010: Washington, DC.
  25. Hoelscher DM, Kirk S, Ritchie L, Cunningham-Sabo L, et al., Position of the Academy of Nutrition and Dietetics: interventions for the prevention and treatment of pediatric overweight and obesity. Journal of the Academy of Nutrition and Dietetics, 2013. 113(10): p. 1375-1394.
  26. Wang Y, Wu Y, Wilson RF, Bleich S, Cheskin L, Weston C, Showell N, Fawole O, Lau B, Segal J., What childhood obesity prevention programmes work? A systematic review and meta‐analysis. Obesity Reviews, 2015. 16(7): p. 547-565.
  27. Sobol‐Goldberg S, Rabinowitz J, and Gross R, School‐based obesity prevention programs: A meta‐analysis of randomized controlled trials. Obesity, 2013. 21(12): p. 2422-2428.