Causes of rising obesity

Although the connection isn't a simple straight line, Drewnowski see roots in three changes:

  • Rising costs and stagnant wages. Salaries haven't kept up; single salaries rarely can support families as they commonly did 50 years ago.
  • Changing jobs. The switch from manufacturing to a service economy reduced the number of stable, well-paid 9-to-5 jobs. Lower-paid shift work, now prevalent, pays less and makes it hard to schedule regular mealtimes.
  • Working women. Fast-food restaurants are blamed a lot for obesity; the huge change in U.S. households stemming from the large-scale entry of women into the workforce in the past 50 years gets less attention.

Not everyone who is at risk is obese. There are other factors -- including genetics, emotions, psychology and metabolism -- although they appear to play smaller parts.

Townsend is interested in the minority who stay lean on tight food budgets. Immigrants from Asian countries, for example, largely resist obesity despite low incomes. In subsequent generations, however, Asian-Americans have joined the epidemic.

How to stay thin on a lean budget

The immigrants' secret? It's basic, says Townsend: They cook from scratch.

You can eat well without cooking at home. But it's expensive. Americans consume about a third of our calories away from home, according to University of Washington epidemiologist Barbara Bruemmer.

People trying to eat healthy on a low budget have no choice but to cook from scratch, Townsend says. But for many, it's not easy -- or even possible. Cooking from basic ingredients is nearly a lost art among large numbers of Americans because of a lack of training, time and organizational skills, she says.

When Townsend interviews people, she asks if they cook meals at home. Sure they do, many say. But it turns out that what they mean is that they're combining boxed ingredients or reheating processed food in a microwave.

"Changing is so much work," says Townsend. Taste buds attuned to fatty, salty, sugary fast foods and processed foods must be retrained. Processed foods combine cheap ingredients -- corn syrup, refined grains and fats -- and sophisticated chemical research for addictive eating experiences.

A bowl of homemade soup filled with vegetables and subtler flavors has trouble competing. It's often not realistic to expect people stuck in difficult lives with few good solutions to become enthusiastic about changing their diets.

Fast food isn't just nutrition; it's also cheap, satisfying entertainment. "And it's one of the few things that less-well-off people have: They don't have to cook," Julie Guthman, an associate professor of community studies at the University of California, Santa Cruz, told The New York Times. She's the author of "Weighing In: Obesity, Food Justice, and the Limits of Capitalism."

The federal food stamp program, now called SNAP (Supplemental Nutrition Assistance Program), is trying a $20 million pilot program in Hampton County, Mass., to see if incentives can entice users to buy fruits, vegetables and other healthful foods.

Townsend's solution is simpler and more radical: Revamp SNAP so it can be used to purchase only ingredients -- no prepared foods, prepared ingredients, snacks or soda pop.

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"The intent of the (food stamp) program, when it was established in the 1930s, was to help people buy ingredients that they would in turn use to cook at home," she says.

Drewnowski has another solution: Bring home-economics classes back to schools. "It would do more for obesity prevention than any other thing," he believes.

While the experts wrestle with big-picture solutions, you can start here: