A post by Nina Lincoff which has been making the rounds notes that fast-food eating isn’t a poor habit, but a lower-middle and middle-class habit:

It’s trendy to blame fast food for the alarming obesity rate among poor Americans. But a new study shows that the largest population of eaters venturing out to Burger Kings, Chick-fil-As, and Taco Bells are those on the lower rungs of the middle class.

According to researchers from the University of California at Davis, the sweet spot for fast-food franchises are upwardly mobile consumers moving from the lowest income bracket to middle one. In a study of about 5,000 adults, DaeHwan Kim and J. Paul Leigh found that the relationship between fast-food eating and income looks less like a negative linear relationship—where the lower one’s income, the more fast food they eat—and more like an “inverted U.” Patronage of fast-food restaurants increases as families move out of the low-income bracket, peaks in the lower regions of the middle-income population, then declines after families begin to earn more than $60,000 annually.

One thing to note here, however, is the notion of downward mobility: many middle class households, especially at the low end, will have been poor at some point. I don’t want to give the impression that I think as soon as your income drops below a certain level, you enter I CAN HAZ CHEEZBURGER!! territory. But we should recognize that in our current economy, what a poor household is can be a very fluid thing.