That's the title of a recent blog post from Paul Levy, in which he notes the ludicrous state of the average American meal. "A single sandwich with 1500 calories. A 32-ounce drink from the soda fountain with hundreds more."
One commenter notes that it take more time and money to eat healthy than to eat nutrition-free junk. My response: Of course, part of the reason it costs more to eat healthy than eat junk is U.S. government food policy. Why is it that tobacco and corn production are subsidized but fruit and vegetables are not?
A lot of this is culture - many parts of our society are conditioned to value quantity over quality, so a gigantic plate of mediocre food is "better" than a smaller portion of quality food.
Few of us are taught to value fresh ingredients and quality meals, or the effort that goes into making them. Michael Pollan has some excellent analysis of this in "In Defense of Food."
And, as I noted in a Facebook post responding to the issue of a sedentary society, many Americans' environment makes it all but impossible to walk anywhere. New development patterns cordon off commercial from residential, which means most people can't walk to walk to a grocery store. Most new schools are sited in ways that make it dangerous for kids to walk.
I work less than a mile from major retail centers, but the suburban development patterns are such that you take your life in your hands if you try to make the trip by foot. It's crazy.
It would be illegal under most modern zoning codes to design a pedestrian-friendly development patterned after one of America's great walkable neighborhoods like Boston's Back Bay.