Causes of Childhood Obesity
As with adult-onset obesity, childhood obesity has multiple causes centering around an imbalance between energy in (calories obtained from food) and energy out (calories expended in the basal metabolic rate and physical activity). Childhood obesity most likely results from an interaction of nutritional, psychological, familial, and physiological factors.
Foodfacts.com has learned that the risk of becoming obese is greatest among children who have two obese parents. This may be due to powerful genetic factors or to parental modeling of both eating and exercise behaviors, indirectly affecting the child’s energy balance. One half of parents of elementary school children never exercise vigorously.
The average American child spends several hours each day watching television; time which in previous years might have been devoted to physical pursuits. Obesity is greater among children and adolescents who frequently watch television, not only because little energy is expended while viewing but also because of concurrent consumption of high-calorie snacks. Only about one-third of elementary children have daily physical education, and fewer than one-fifth have extracurricular physical activity programs at their schools
Since not all children who eat non-nutritious foods, watch several hours of television daily, and are relatively inactive develop obesity, the search continues for alternative causes. Heredity has recently been shown to influence fatness, regional fat distribution, and response to overfeeding. In addition, infants born to overweight mothers have been found to be less active and to gain more weight by age three months when compared with infants of normal weight mothers, suggesting a possible inborn drive to conserve energy
Treatment of Childhood Obesity
Obesity treatment programs for children and adolescents rarely have weight loss as a goal. Rather, the aim is to slow or halt weight gain so the child will grow into his or her body weight over a period of months to years. It is estimated that, for every 20 percent excess of ideal body weight, the child will need one and one-half years of weight maintenance to attain ideal body weight.
Early and appropriate intervention is particularly valuable. There is considerable evidence that childhood eating and exercise habits are more easily modified than adult habits. Three forms of intervention include:
Adopting a formal exercise program, or simply becoming more active, is valuable to burn fat, increase energy expenditure, and maintain lost weight. Most studies of children have not shown exercise to be a successful strategy for weight loss unless coupled with another intervention, such as nutrition education or behavior modification. However, exercise has additional health benefits. Even when children’s body weight and fatness did not change following 50 minutes of aerobic exercise three times per week, blood lipid profiles and blood pressure did improve.
Fasting or extreme caloric restriction is not advisable for children. Not only is this approach psychologically stressful, but it may adversely affect growth and the child’s perception of “normal” eating. Balanced diets with moderate caloric restriction, especially reduced dietary fat, have been used successfully in treating obesity. Nutrition education may be necessary. Diet management coupled with exercise is an effective treatment for childhood obesity.
Many behavioral strategies used with adults have been successfully applied to children and adolescents: self-monitoring and recording food intake and physical activity, slowing the rate of eating, limiting the time and place of eating, and using rewards and incentives for desirable behaviors. Particularly effective are behaviorally based treatments that include parents. Problem-solving exercises have been used in a parent-child behavioral program and found children in the problem-solving group, but not those in the behavioral treatment-only group, significantly reduced percent overweight and maintained reduced weight for six months. Problem-solving training involved identifying possible weight-control problems and, as a group, discussing solutions.
Prevention of Childhood Obesity
Obesity is easier to prevent than to treat, and prevention focuses in large measure on parent education. In infancy, parent education should center on promotion of breastfeeding, recognition of signals of satiety, and delayed introduction of solid foods. In early childhood, education should include proper nutrition, selection of low-fat snacks, good exercise/activity habits, and monitoring of television viewing. In cases where preventive measures cannot totally overcome the influence of hereditary factors, parent education should focus on building self-esteem and address psychological issues.