Americans eat too much, exercise too little and as a result are too fat. Not everybody is obese, but enough people to call it a crisis. Moreover, America's obesity problem has become a metaphor for our economic troubles: We are simply too flabby to compete in a cutthroat global economy.

However, instead of seeing obesity as a problem, maybe it's time we recognized it as an opportunity—the rare chance for the United States to dominate a new industry. The bad news is a whopping 30 percent of Americans are obese, up 14 percent from the early 1970s. Obesity-related medical costs are $100 billion, almost as much as those from tobacco; and half of these costs were picked up by the public in the form of Medicare and Medicaid. According to the American Medical Association obesity causes about 112,000 premature deaths annually. Moreover, there are almost as many fat kids as adults.

The good news is we are ahead of the curve. The world may be getting flatter, but it is also getting fatter. Our head start in chubbiness gives us the chance to dominate the dynamic fat economy. Our competitive disadvantage in the gym could ultimately be a competitive advantage in the international fatness marketplace.

The beauty of the American economy is the way companies large and small nimbly adjust to meet the demands of consumers. So it is no surprise that new businesses have arisen to serve the our fattening population: surgery practices that focus on liposuction and gastric reduction, weight loss clinics and gyms, health food stores and diet pill purveyors, personal trainers and WeightWatchers; there are even fat friendly reality TV shows. Size-friendly travel agencies advise overweight vacationers on how to avoid being charged for two airplane seats and how to find the most accommodating cruise lines and resorts. There are dating services, too, and the number of accredited U.S. weight-loss camps has nearly doubled in the past five years. The women's gym Curves has an astonishing 9,000 franchises.

Next, consider some of the aspects of the fat economy that make it economically promising for the United States. This is a market that has been growing rapidly despite the billions spent on weight loss. Obesity is a condition that can last for a lifetime and hence requires a lot of spending on maintenance, year after year. And the fat industry revolves around the sorts of things that the U.S. still does better than anybody else: creating services, delivering health advice, concocting diet plans and fitness regimens, and developing lifestyle brands. Even better, a lot of these services and products can be exported. Curves has already expanded to 28 countries. The South Beach Diet has been translated into at least two dozen foreign languages.

The United States clearly has a head start in fatonomics. Obesity is a byproduct of many complex factors, ranging from genetics to psychology. But fast-food restaurants, sugar-laden drinks, and the availability of massive quantities of cheap food have all played important roles in making Americans heavier. So with any luck, the rest of the world will be porking up soon. After all, which American companies have been forging ahead aggressively in foreign markets? McDonald's, Coca-Cola, and Wal-Mart; their expansion should not only fatten the pockets of U.S. investors, they should also help fatten the local populations. It's only a matter of time before China and India start to lose their battles with the bulge. And where will they look for quack potions, quick-fix diets and expensive surgeries?

For decades, physical fitness has been equated with national purpose. Today our wannabe-buff president—and our far more buff governor of California—routinely exhort the nation to exercise, lose weight, and eat right. On the whole, they're right. Obesity is bad for the nation's health. But is it entirely bad for the nation's economy? In its own chucky way, this national epidemic is bringing out the best in American innovation and entrepreneurship.