There are many causes of childhood obesity. Overweight in children and adolescents is generally caused by a lack of physical activity, unhealthy eating patterns resulting in excess energy intake, or a combination of the two. Genetics and social factors, socioeconomic status, race/ethnicity, media and marketing, and the physical environment also influence energy consumption and expenditure. Most factors of overweight and obesity do not work in isolation and solely targeting one factor may not make a significant impact on the growing problem.
Nutrition and Eating Habits
Children and adolescents are eating more food away from home, drinking more sugar- sweetened drinks and snacking more frequently. Convenience has become one of the main criteria for Americans’ food choices today, leading more and more people to consume “away-from-home” quick service or restaurant meals, or to buy ready-to-eat, low cost, quickly accessible meals to prepare at home.
Physical Inactivity and Sedentary Behaviors
Watching television, using the computer and playing video games occupy a large percentage of children’s leisure time, influencing their physical activity levels. It is estimated that children in the United States are spending 25 percent of their waking hours watching television. Statistically, children who watch the most hours of television have the highest incidence of obesity. v,vi This trend is apparent not only because little energy is expended while viewing television but also because children are prone to eating high-calorie snacks while watching television.
Physical Environment
In urban and suburban areas, the developed environment can create obstacles to being physically active. In urban areas, space for outdoor recreation can be scarce, preventing children from having a protected place to play. Neighborhood crime, unattendeddogs or lack of street lighting may also inhibit children from being able to walk safely outdoors. Busy traffic can prevent children from walking or biking to school as a means of daily exercise.
Socioeconomic Status and Race/Ethnicity
The prevalence at which obesity has been increasingin children in the recent years has been even morepronounced and rapid among minority children.Between 1986 and 1998, obesity prevalence amongAfrican Americans and Hispanics increased 120percent, as compared to a 50 percent increase amongnon-Hispanic Whites.vii The relationship among race/ethnicity, socio-economic status, and childhood obesity may result from a number of underlying causes, including less healthy eating patterns (e.g., eating fewer fruits and vegetables, more saturated fats), less physical activity, more sedentary behavior, and cultural attitudes about body weight. viii Clearly these factors tend to co-occur and are likely to contribute to the increased risk of obesity in children.
Parental Influences
Numerous parental influences shape the eating habits of youth. Several studies suggest that breast-feeding offers a small but consistent protective effect against obesity in children.
  • Constraints on parents’ time potentially contribute to children’s weight problems, as working parents probably rely more heavily than non-working parents on prepared, processed and fast-foods, which generally have high calorie, high fat and low nutritional content.
  • Children left unsupervised after school may make poor nutritional choices and engage in more sedentary activities.
  • Child care providers may not offer as many opportunities for physical activity and may offer less nutritious food alternatives.
The recent social and economic changes in American society have encouraged the consumption of excess energy and have had a detrimental effect on energy expenditure among youth. These changes have impacted the foods available in the homes and the degree of influence parents have when children make food selections, and have led to increases in sedentary behaviors among youth.
Research shows that there are a number of root causes of obesity in children. Selecting one or two main causes or essential factors is next to impossible because the potential influences on obesity are multiple and intertwined. However, the fundamentals are clear: to stay healthy, children should eat a balanced diet and devote adequate time to physical activity.
The information in this section was summarized from the U.S. Department of Health and Human Services. For the complete text, please visit: