"Not only has the cost of food dropped, but it has become even more available," An said. "So a smaller share of Americans' disposable income now buys many more calories."
The decline of food expenditures relative to income becomes more dramatic when considering quality factors, such as greater convenience, reduced time needed for preparation, increased variety and the ubiquitous availability of food.
Sturm and An say that effective economic policies to curb obesity remain elusive.
Imposing taxes on foods with low-nutritional value could nudge behavior toward healthier diets, as might subsidies or discounts for healthier foods. But political and popular support for such approaches has been low.
For example, Denmark imposed a tax on foods high in saturated fats in 2011, only to repeal the move a year later. In the United States, there have been numerous legislative proposals to tax soft drinks or junk food, but no meaningful plans have passed to date.
"The high cost of healthy food may not be the problem as far as obesity is concerned, rather it is the excess availability and affordability of all types of food," Sturm said. "We need to consider strategies that replace calorie-dense foods with fruits and vegetables, rather than just add fruits and vegetables to the diet."
|Contact: Warren Robak|