William Dietz, the CDC's director of the Division of Nutrition and Physical Activity, couldn't agree more. "It's not just a medical problem," he says. "It has medical implications, but the rapid rise in obesity has obviously been caused by environmental factors." By focusing only on the medical, he continues, "we neglect the broader context in which obesity has occurred and in which we have to treat it."

Dietz, a pediatrician who has studied childhood overweight for decades, says the problem didn't get much attention until the late 1990s, when the CDC began releasing data showing a surge in Americans' weight. Sometime after that, he says, scientific interest broadened from the nutritional arena to other research fields, including sociology and economics. The expanded interest has been important, Dietz says, because involving more academic disciplines has boosted the odds that a solution will be found.

Researchers at MU are prepared to search for multidisciplinary solutions. Among their more noteworthy recent efforts was an investigation conducted by Gable and her colleague Susan Lutz, then assistant professor in MU's dietetics program, published in the journal Family Relations. The study assessed how various family and home-life factors influence a child's risk for unhealthy weight gain.

Specifically, Gable and Lutz's analysis sought to determine how family composition and income, food availability, parenting beliefs and attitudes, and childrens' diet and activities affect a child's weight. The two researchers first looked for relationships among the various categories. Parents who reported having more family meals, for example, tended to keep more fruits and vegetables in their homes. Parents who said they knew little about preparing nutritious meals, on the other hand, tended to have fewer healthy products in their homes. Perhaps not surprisingly, parents who reported a greater availability of sweet or salty snacks said their kids ate more junk food.

Although these associations do not directly link any activity with unhealthy weight gain, Gable says they are essential to understanding the contexts of childhood overweight. "These relationships open the door on the processes at work, or how a person might acquire bad habits that lead to overweight," she says.

With this background data, Gable and Lutz next examined how other factors might influence children's weight. They found that a parent's race, education or type of employment was not predictive of weight problems. But kids in lower-income homes tended to be heavier. So did kids living with an unmarried adult.