Why Are People Getting Fatter? Ask An Economist.

Why is obesity increasing? Is less exercise to blame, or is the cause increased food consumption?

Researchers from both Harvard's Global Health Initiative and the economics department looked at data for developed countries and point the finger at increased caloric intake. In a new paper, "Why is the Developed World Obese," they say that people are eating more because of falling food prices, increased urbanization, and higher female work force participation. The shift to mass-produced foods that are quick to prepare has not been good for body mass indices.

The findings confirmed an earlier study by some of the same authors that focused solely on obesity among Americans. That 2003 work also found that increased energy input was the principal culprit. While caloric expenditure has not changed much since 1980, intake has increased "markedly."

That jump in consumption, in turn, was due to the advent of mass-produced and mass-marketed foods, with lower costs in both real dollars and in time spent preparing and cooking. As with any good, lower costs lead to increased use -- in this case, more eating.

David Cutler, Edward Glaeser, and Jesse Shapiro cited the potato chip -- once scarce due to the effort and equipment required to peel, cut, and fry them. Centralized production, refrigerated transportation, and advances in restaurant and hompe preparation mean that "the French fry is the dominant form of potato and America’s favorite vegetable. ... From 1977 to 1995, total potato consumption increased by about 30 percent, accounted for almost exclusively by increased consumption of potato chips and French fries."

Goodbye, mashed potato.

Other studies have found that snacks account for virtually all the increase in caloric consumption, with changes in 'real' meals netting out to a slight decrease from the mid-1970's to the mid-1990's.

Among the interesting facts Cutler, et al found:

"consumption of mass produced food has increased the most in the past two decades ...

... groups in the population that have had the most ability to take advantage of the technological changes have had the biggest increases in weight. Married women spent a large amount of time preparing food in 1970, while single men spent little. Obesity increased much more among married women.

... obesity across countries is correlated with access to new food technologies and to processed food ...

... increases in weight have been biggest at the upper end of the weight distribution, where self-control problems are the most severe.

...food items with large amounts of commercial preparation have increased in
consumption, and food items with less commercial preparation have fallen.

They noted that European countries, which generally have higher food prices and protect small farmers via regulation, are somewhat better off than the U.S., where a more efficient food industry enables consumers to purchase more and more food for the same real cost.