Many things “cause” the obesity epidemic, acting together. But the general consensus around how to respond to this fact has changed significantly.
For years the focus within academic medicine was on changing lifestyle or behavior—in short, approaches that focus on the individual. The approach didn't work very well.
The new approach is to change the default environment that appears to constrain individuals to make bad choices and become obese in the first place by eating more calories than they can burn. A permissive culture that allows even the youngest, most vulnerable children to be bombarded with soda and other junk food ads is one example. Local zoning that leaves many neighborhoods lacking in sidewalks or bike lanes—or virtually any way of getting from point A to B except by car—is another.
But might there be some other mysterious factors like environmental chemicals or contaminated food? Science pointing in that direction is mounting.
This week, Nature reports on a study that looks at the obesity epidemic of the four-legged kind. (Though it’s hard to see how pets and laboratory animals would be as impacted by marketing or zoning as are kids.)
The study, called "Canaries in the Coal Mine," and published in the Proceedings of the Royal Society B, looks at statistics on more than 20,000 animals and finds an epidemic of obesity in family pets, among laboratory animals and even among wild animals living near people.
The study raises as many questions as it answers. The authors acknowledge that there are many conceivable explanations for what they observed. Perhaps rats are fatter because our garbage has become richer as we have. However, an NIH-funded workshop on the “Role of Environmental Chemicals in the Development of Diabetes and Obesity,” is being held January 11–13, 2011in Raleigh, North Carolina.
This promises to be a story we’ll be hearing more about.