ho's to blame for America's obesity epidemic? I think that most people have always believed that overeating demonstrates a lack of self-control. It may be logical to assume that controlling the amount of food eaten is individual responsibility; after all, no one is forcing fat people to overeat. But we're learning more and more about eating practices and what drives people to eat—and it's so much more than a matter of willpower.

Research indicates that obesity and overweight are largely due to environmental factors. Our living, working, eating, and social environments are not the same as they were before the 1970s. Overweight is a social problem that is fostered in part by a culture of convenience and abundance. Our society is creating fat people.

This is the land of plenty, and having plenty of food and plenty of varieties of foods are part of the American Dream. But having too many choices is a major culprit in the overeating epidemic. Research has proven over and over that the larger the variety of foods at a meal, the more adults and children will eat. Think about what happens to you at a buffet: you want to taste everything, which means you need to use several plates or make several trips back to the buffet line just to eat all of the foods you want as part of your meal. If only one or two choices were offered, you would eat significantly less.

Portion size plays a role, too. Portions at restaurants and bakeries, packaged food servings, and cookbook recipe portions have all grown substantially. Restaurants use bigger plates and food containers, and even cup holders in cars have grown to accommodate gigantic drink cups. Studies with children and adults have found that the more food a person is offered, the more they will eat. Kids whose macaroni and cheese portions were doubled at lunchtime ate 25% more than the standard portion they were served the previous day. They took much larger bites when there was more food in front of them, and they did not compensate for the extra calories by eating less at other meals. However, when they were allowed to serve themselves on the third day, the kids only took a standard portion. Kids are supposed to be in touch with their hunger and satiety, but self-regulation only goes so far...

Advertising is another influential factor in our society. Kids are aggressively targeted by television commercials that use their favorite cartoon characters to sell them junk foods, schools that sell sodas and brand-name fast food, and toys and books that carry the names of their favorite food brands. It's not just that this advertising encourages kids to spend their own money—about $30 billion a year—on products they want, but, more importantly, that kids influence their parents to spend about $600 billion a year on products they want. The next generation of eaters understands "freedom of choice" as a decision whether or not to "super size" their fast-food meal.

Price is perhaps the most powerful factor that drives people to choose unhealthy food. Value is a much stronger factor than healthfulness when people are choosing between two foods; the cheaper food, no matter if it's the healthier food or not, is almost always selected. Healthy foods may seem to cost more money, but we need to come up with some creative solutions to get it into peoples' mouths. In France, the obesity rates are very low and the government actually subsidizes vegetables and fruits. The Finnish government recently experimented with offering free salads to restaurant diners. Vegetable consumption vastly increased and heart disease risk factors in the general population were lowered.

There are many factors that contribute to a person being overweight, and I know that a lot of it comes down to self-discipline—you can choose to watch television instead of going for a walk, or to fry the chicken instead of broiling it. But it's important to understand that there are many other external factors that play into this public health epidemic. Obesity is now more than just a personal responsibility, it is a social responsibility that individuals, government, and corporations need to tackle. Recently, when a large chain restaurant executive was asked about his company's new larger breakfast offerings, he stated "the consumer has to decide on moderation. It's not something we can decide." But maybe it should be.