The assumption has always been that the drive-through is a place where people go to feed their families on a budget, but that's not the case

For years the conventional wisdom has been that fast food is poor people's food; that, thanks to government subsidies that ensure cheap calories, the drive-through is where people who can't afford the "good" stuff -- organic, grass-fed, etc. -- go to feed their families on a budget. Why else would anyone eat that stuff?

But a new study to be published in the Journal for Population Health Management reveals the dirty little secret of the American middle class: It's not cash-strapped Americans who are devouring the most Big Macs and Whoppers, it's us! According to the study, a household earning $60,000 a year eats the most fast food, and one bringing in $80,000 is actually more likely to have it their way than one with $30,000. Suddenly, last year's news from the Centers for Disease Control makes sense: Nearly half of obese adults in this country are not poor but middle-class, earning at least $77,000 for a family of four.

The fact is that most people with means, even limited means, will opt for the easiest option come dinnertime.

The unpalatable truth is that fast food's attraction has never really been just about price. For all you hear about the Dollar Menu, a buck at McDonald's buys a small burger, or small fries, or a small drink -- hardly a satisfying meal for most people. As Mark Bittman reported recently in the New York Times, a typical meal for a family of four at McDonald's in Manhattan costs about $28 -- far more than what it would cost to make a healthier meal at home. For someone who's really pinching pennies, a trip to McDonald's makes no sense.

What actually drives families to the drive-through are two simple truths. First, it's convenient. Fast-food hours accommodate odd shifts and offer playrooms to appease screaming children and give moms a break. And, after years of calculated expansion, the restaurants are everywhere we are -- in office buildings, department stores, rest stops, schools, Walmarts, airports, even hospitals -- which makes fast food America's default dining-out option. Second, people like the way fast food tastes. No matter how often or how loudly food crusaders preach about the nasty and ecologically disastrous bits that end up in those burgers, fast food's carefully calibrated mix of salt and fat is hard for many to resist.

This is problematic for food reformers, in part because their advocacy on behalf of the poor has afforded them at least some political cover against charges of elitism. But it also deeply complicates the question of how to tackle the obesity crisis, which costs Americans $150 billion annually. The fact is that most people with means, even limited means, will opt for the easiest option come dinnertime. And that's eating out, not shopping, cooking, and cleaning up at home, which foodies claim as the Holy Grail. In most places, hard as it may be for some to believe, eating out usually means some version of fast food. It's often the only option.

Figuring out how to make healthier food rival the drive-through for convenience and taste will be hard enough. Convincing people to choose it over the bad stuff they love will require a monumental cultural shift, the kind that is likely to take generations. It will require a careful, clever mix of coercion -- soda taxes or health-care penalties for the unhealthy -- education, and persuasion. It gives a whole new meaning to the term "slow food."

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