General Discussion
In reply to the discussion: Modern wheat a "perfect, chronic poison," doctor says [View all]hedgehog
(36,286 posts)refers to an abrupt spike in obesity in the period 1988-1991:
"When a respected academic journal calls something dramatic, it's the equivalent of a red alert. The results were consistent virtually across the board - among men and women, young and old, black and white. The rate of obesity in America had evidently exploded."
http://www.amazon.com/The-End-Overeating-Insatiable-American/dp/B004NSVE32#reader_B004NSVE32
Ironically, I think Dr. Kessler's entire book was on the wrong track after that. He listed several causes for obesity in America, but failed to show that they linked to the 1988-1991 time frame. I would say that we need to look at, say 1985 forward and see what was different from the preceding years. It's possible that there is no single cause, but a perfect storm of all the causes listed in the OP plus the introduction of GMO foods plus environmental exposures to chemicals such as BPA.