Children who gain weight eat more calories than they use up each day. The ones who gain weight the fastest eat relatively more high-calorie foods such as hamburgers, French fries, and other fast foods. They also exercise less, preferring to spend more of their time watching TV and playing video games rather than playing outdoors and participating in sports.

Traditionally, mothers have taken responsibility for making the choices about what foods children eat and the scope of their outdoor activities. As compared to the 1960s, when about one-half of mothers worked outside the home, more than three-fourths do so today. These mothers have less time to keep their children from eating too much (e.g., in the hours after school before getting home from work) and to take them to playgrounds to exercise. This helps explain why only 8 percent of children whose mothers have never worked outside the home are obese as compared to 17 percent among children whose mothers work full-time. It is important to realize that children have always had an incentive to eat sweet snacks and tasty high-calorie foods and engage in sedentary activities; it is now also true that parents have economic incentives that affect the time they have available to devote to child rearing. Finally, our society has developed a taste for bigger houses with more expensive furnishings and bigger, more expensive cars.

From an economic standpoint, is it possible that some parents effectively make a choice to have bigger, more expensive houses, cars, furnishings, and overweight children?