Recent statistics hint that the American obesity epidemic is slowing down, but even if  the trend stops growing entirely, our country will be left with more than half of its population overweight. A new strategy from the American Heart Association, outlined in the July issue of Circulation, posits that attempts to get individuals to consciously change their own behavior can only get so far. The lead author, Dr. Shiriki Kumanyika makes the case for a population-based strategy that modifies the external factors that facilitate or hinder the daily steps towards health.

The population-based plan calls for reengineering society so that healthy behavior becomes easier. Primarily, this means working to make sure that nutritious food and frequent exercise fit naturally into our lives.

Diets are notoriously hard to stick to using pure willpower, but the task becomes much easier if your attention is not grabbed by fatty food on display all around you. Many municipal governments are already engaged in city-wide projects to get rid of things like trans-fat and subsidize fruit and vegetable stands in the streets. Much of our food consumption is triggered by proximity and convenience; if the hot dog vender on your way to work has been replaced by a fruit-stand, it will be much easier to eat nutritiously.

While there has been some success with these efforts, a more coordinated national plan may be required to reengineer some of the systems that funnel us into overeating. Better nutrition labels, greater restrictions on advertising and fast-food locations, and subsidies for healthy vendors are all possible with the power of the federal government.

The second major topic that Dr. Kumanyika focuses on is encouragements for physical activity. American culture values labor-saving devices and cars, while looking down on adults who want to ride bikes to work. These underlying values subtly dissuade citizens from taking the stairs or biking to work. If we can change the values, say by romanticizing those who use muscles instead of gasoline, then many more people will consider exercise a natural part of their daily lives. In addition to this cultural reprogramming, civil engineering may also help by modifying the city infrastructure to encourage activity, for example by widening sidewalks.

The population-based approach can reduce obesity without requiring great effort from individual citizens. To give an extreme example, in a city that bans automobiles and fatty foods, even the laziest citizens will find it easy to maintain a health weight. Hopefully, a combination of educating individuals and engineering their environments will reverse the out-of-control weight gains of the past few decades.