According to Forbes: "Researchers have found that [Memphis] residents are aware of the area's obesity problem, currently affecting 34 percent of its population. Among the causes they blame: high rates of poverty and a culture of Southern hospitality and food that values certain types of dishes--many of them fried--over healthier choices. Memphis actually sits on the western edge of a web of Southern cities along with Birmingham, Ala., and Atlanta, that also landed on our list."
To read more about the survey's methodology (hanging out at Tops Barbecue?) and to see a list of America's fattest cities (in pictures, yet), check out Forbes.com.
For a more serious look at the problem, see Preston Lauterbach's story from June's Memphis magazine.