• Childhood obesity has more than doubled in children and quadrupled in adolescents in the past 30 years.^{1, 2}
• The percentage of children aged 6–11 years in the United States who were obese increased from 7% in 1980 to nearly 18% in 2012. Similarly, the percentage of adolescents aged 12–19 years who were obese increased from 5% to nearly 21% over the same period.^{1, 2}
• In 2012, more than one third of children and adolescents were overweight or obese.¹
• 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.