Contrary to popular wisdom, eating at McDonald’s isn’t exactly cheap, costing some $28 for a family of four. Which might help explain the results of a recent study from the University of California, Davis, which found that people’s visits to fast-food joints increased along with their incomes, and that poor people were spending fewer dollars on fast food than lower-middle and middle-income Americans.
The authors said their study suggests that the availability of fast food isn’t the only driver of obesity in poor groups. “There is a correlation between obesity and lower income, but it cannot be solely attributed to restaurant choice,” said J. Paul Leigh, professor of public health sciences at U.C. Davis and senior author of the study, in a statement. “Fast-food dining is most popular among the middle class, who are less likely to be obese.