Childhood Obesity Facts

Childhood obesity has more than tripled in the past 30 years.
The percentage of children aged 6–11 years in the United States who were obese increased from 7% in 1980 to nearly 20% in 2008. Similarly, the percentage of adolescents aged 12–19 years who were obese increased from 5% to 18% over the same period.
In 2008, more than one third of children and adolescents were overweight or obese.^1,2
Overweight is defined as having excess body weight for a particular height from fat, muscle, bone, water, or a combination of these factors.³ Obesity is defined as having excess body fat.⁴
Overweight and obesity are the result of “caloric imbalance”—too few calories expended for the amount of calories consumed—and are affected by various genetic, behavioral, and environmental factors.^5,6

Health Effects of Childhood Obesity

Childhood obesity has both immediate and long-term effects on health and well-being.
Immediate health effects:

Obese youth are more likely to have risk factors for cardiovascular disease, such as high cholesterol or high blood pressure. In a population-based sample of 5- to 17-year-olds, 70% of obese youth had at least one risk factor for cardiovascular disease.⁷
Obese adolescents are more likely to have prediabetes, a condition in which blood glucose levels indicate a high risk for development of diabetes.^8,9
Children and adolescents who are obese are at greater risk for bone and joint problems, sleep apnea, and social and psychological problems such as stigmatization and poor self-esteem.^5,6,10

Long-term health effects:

Children and adolescents who are obese are likely to be obese as adults^11-14 and are therefore more at risk for adult health problems such as heart disease, type 2 diabetes, stroke, several types of cancer, and osteoarthritis.⁶ One study showed that children who became obese as early as age 2 were more likely to be obese as adults.¹²
Overweight and obesity are associated with increased risk for many types of cancer, including cancer of the breast, colon, endometrium, esophagus, kidney, pancreas, gall bladder, thyroid, ovary, cervix, and prostate, as well as multiple myeloma and Hodgkin’s lymphoma.¹⁵

Prevention

Healthy lifestyle habits, including healthy eating and physical activity, can lower the risk of becoming obese and developing related diseases.⁶
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.
Schools play a particularly critical role by establishing a safe and supportive environment with policies and practices that support healthy behaviors. Schools also provide opportunities for students to learn about and practice healthy eating and physical activity behaviors.

Key Resources

References

Ogden CL, Carroll MD, Curtin LR, Lamb MM, Flegal KM. Prevalence of high body mass index in US children and adolescents, 2007–2008. Journal of the American Medical Association 2010;303(3):242–249.
National Center for Health Statistics. Health, United States, 2010: With Special Features on Death and Dying. Hyattsville, MD; U.S. Department of Health and Human Services; 2011.
National Institutes of Health, National Heart, Lung, and Blood Institute. Disease and Conditions Index: What Are Overweight and Obesity? Bethesda, MD: National Institutes of Health; 2010.
Krebs NF, Himes JH, Jacobson D, Nicklas TA, Guilday P, Styne D. Assessment of child and adolescent overweight and obesity. Pediatrics 2007;120:S193–S228.
Daniels SR, Arnett DK, Eckel RH, et al. Overweight in children and adolescents: pathophysiology, consequences, prevention, and treatment. Circulation 2005;111;1999–2002.
Office of the Surgeon General. The Surgeon General's Vision for a Healthy and Fit Nation. [pdf 840K]. Rockville, MD, U.S. Department of Health and Human Services; 2010.
Freedman DS, Zuguo M, Srinivasan SR, Berenson GS, Dietz WH. Cardiovascular risk factors and excess adiposity among overweight children and adolescents: the Bogalusa Heart Study. Journal of Pediatrics 2007;150(1):12–17.
Li C, Ford ES, Zhao G, Mokdad AH. Prevalence of pre-diabetes and its association with clustering of cardiometabolic risk factors and hyperinsulinemia among US adolescents: NHANES 2005–2006. Diabetes Care 2009;32:342–347.
CDC. National diabetes fact sheet: national estimates and general information on diabetes and prediabetes in the United States, 2011 [pdf 2.7M]. Atlanta, GA: U.S. Department of Health and Human Services.
Dietz WH. Overweight in childhood and adolescence. New England Journal of Medicine 2004;350:855-857.
Guo SS, Chumlea WC. Tracking of body mass index in children in relation to overweight in adulthood. American Journal of Clinical Nutrition 1999;70:S145–148.
Freedman DS, Kettel L, Serdula MK, Dietz WH, Srinivasan SR, Berenson GS. The relation of childhood BMI to adult adiposity: the Bogalusa Heart Study. Pediatrics2005;115:22–27.
Freedman D, Wang J, Thornton JC, et al. Classification of body fatness by body mass index-for-age categories among children. Archives of Pediatric and Adolescent Medicine 2009;163:801–811.
Freedman DS, Khan LK, Dietz WH, Srinivasan SA, Berenson GS. Relationship of childhood obesity to coronary heart disease risk factors in adulthood: the Bogalusa Heart Study. Pediatrics 2001;108:712–718.
Kushi LH, Byers T, Doyle C, Bandera EV, McCullough M, Gansler T, et al. American Cancer Society guidelines on nutrition and physical activity for cancer prevention: reducing the risk of cancer with healthy food choices and physical activity. CA: A Cancer Journal for Clinicians 2006;56:254–281.