No, not really Jim Fallows, but a judicious and ordered sampling of the many--"unprecedented," he calls it--letters he received in response to a fairly offhand observation he made, one of an omnibus roundup, on what he sees here now that he's back after living in China for three years.
No need to repeat his grouping by topic, but I will ask the farm-minded among you to consider in particular the letter from the Vermont city-dweller-turned-farmer, puzzled that the rigors of rural life, even for the non-farmer, don't prevent a high number of obese people, even though access to fast food is relatively difficult.
Ruralites (as opposed to urbanites), please weigh in: do you, like the writer, notice an increase in sheer physical labor in the country, vs the city or the suburbs? Or is all travel done in the car, and does all travel bring one beside various fast-food outlets and stores selling the processed foods that other writers posit are the main culprit?
Obesity as perhaps today's most obvious marker of class bifurcation is by now a given. Have a look at the absorbing theories Fallows's correspondents offer as to why. Then more of your own, please.