The obesity epidemic is among the most critical health issues facing the United States. Although it has generated a lot of attention and calls for solutions, it also has served up a super-sized portion of myths and misunderstandings.

 

 

As obesity rates have soared, some researchers have focused on individuals' genetic⁵ predisposition for gaining weight. Yet, between 1980 and 2000, the number of Americans who are obese has doubled -- too quickly for genetic factors to be responsible.

 

So why do we eat more than we need? The simple answer: Because we can. At home and at restaurants, a dollar puts more calories on our plates than ever before. Before World War II, the average family spent as much as 25 percent of its total income on food -- in 2011, it was 9.8 percent. And people eat out now more than in the past. In 1966, the average family spent 31 percent of its food budget dining away from home -- in 2011, it was 49 percent. Because restaurant meals usually have more calories than what we prepare at home, people who eat out more frequently have higher rates of obesity than those who eat out less.

 

 

According to a 2006 study, "research on restrained eating has proven that in most circumstances dieting is not a feasible strategy." In other words: People won't lose weight by trying to eat less because they can't easily control themselves. Unfortunately, this puritanical⁶ view of personal resolve plays down how our surroundings and mental state determine what we eat.

 

Research shows that if we are overwhelmed with too much information or preoccupied⁷, we have a tendency to surrender to poor dietary choices. In one study, for example, people asked to choose a snack after memorizing a seven-digit number were 50 percent more likely to choose chocolate cake over fruit salad than those who had to memorize a two-digit number. When adults in another study were asked to sample a variety of foods after watching a television show with junk-food commercials, they ate more and spent a longer time eating than a similar group watching the same show without the junk-food ads. In the same study, children ate more goldfish crackers⁸ when watching junk-food commercials than those who saw other ads.

 

 

Obesity is usually the consequence of eating too much junk food and consuming portions that are too large. People may head to the produce section of their grocery store with the best intentions, only to be confronted by candy at the cash register and chips and soda⁹ at the end of aisles¹⁰. Approximately 30 percent of supermarket sales are from such end-of-aisle locations. Food retailers¹¹' impulse-marketing¹² strategies contribute significantly to obesity across the population, not just for those who do not live near a green grocer or can't afford sometimes pricier healthy choices.

 

 

There is compelling evidence that the increase in calories consumed explains the rise in obesity. The National Health and Nutrition Examination found that people take in, on average, more than 500 more calories per day now than they did in the late 1970s, before obesity rates accelerated.That's like having Christmas dinner twice a week or more. It wouldn't be a problem if we stuffed ourselves only once a year, but all-you-can-eat feasts are now available all the time. It's nearly impossible for most of us to exercise enough to burn off these excess calories.

 

 

Even with more information about food, extra-large portions and sophisticated marketing messages undermine our ability to limit how much we consume. Consider Americans' alcohol consumption: Only licensed¹³ establishments can sell spirits to people older than 21, and no alcohol can be sold in vending¹⁴ machines. Yet there are very few standards or regulations to protect Americans from overeating.

 

In the 19th century, when there were no controls on the quality of drinking water, infectious disease was a major cause of death. Once standards were established, the number of these fatalities¹⁵ plummeted¹⁷.

 

Similarly, if Americans did not live in a world filled with buffets¹⁸, cheap fast food, soft drinks with corn syrup¹⁹, and too many foods with excess fat, salt and sugar, the incidence of obesity, heart disease, high blood pressure and diabetes²⁰ probably would plummet¹⁶. Education can help, but what’s really needed is regulation -- for example, limits on marketing that caters²¹ to our addiction²² to sugar and fat.

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