Big-box retailers like Costco, Sam's Club, BJ's Wholesale and Walmart, and fast-food restaurants, have been blamed for the rise in obesity among people, claims a new study.
Courtemanche, an assistant professor at the Andrew Young School of Policy Studies at Georgia State University, said that though people's eating habits had increased, as economists, they knew that preferences didn't change overnight, and hence the steady rise since 1980 must involve their incentives to eat.
This question led Courtemanche and his colleagues to build a comprehensive economic model of body weight and 27 state-level variables they categorized as general economic conditions (unemployment and income) and labor supply, as well as the monetary or time costs associated with calorie intake (food prices, retail presence), physical activity (gasoline prices, fitness centers) and smoking.
Courtemanche said that the changes in variables related to calorie intake collectively explains 37 percent of the rise in body mass index (BMI) rates and 43 percent of the rise in obesity. And as per their data, the pervasive presence of supercenters, warehouse clubs and restaurants were responsible for most of these gains.
Fitness centers and rising gas prices were found to work against the rise in BMI.
The shrinking proportion of blue-collar workers and rise in food stamp benefits also contribute to the nation's rising obesity, the data suggest this effect is not due to differences in on-the-job physical activity.
Courtemanche said that the best explanation for the difference between these workers, outside of physical movement, was time flexibility. White-collar workers have the flexibility to graze all day at their desks, and they can take lunch out. It all points to caloric intake.
The research is published by the National Bureau of Economic Research.