Agreed. There is a 10 percentage point difference in obesity between those who make the most and those who make the least - 20% obesity for the richest and 30% for the least wealthy. That's not a very convincing argument to me that people are so behaviorally different. Alot of middle class obese people are in heavy denial about whose problem it is, frankly. I think it's another case of "if you say it enough, and get enough funding to deal with the "problem", it has to be true (that poor people are fat and lazy). I'm not pointing fingers at anyone here, but just wanting to remind folks to be at least as critical of these studies and their conclusions as we are of dietary recommendations.