http://abcnews.go.com/Health/Diet/st...C-RSSFeeds0312
I was thinking of putting this in the paranoia section, but it just might make sense. The rise in obesity occurred right about the time that AC became more widespread. What effect does heat have on your metabolism? Are you less likely to eat large meals when it is 90+ F(37+ C)? And do you burn off more calories trying to keep cool on a hot day, or in a building without AC? And does your body purposely store fat when it's cold out and lose it when it is hot? Are there more overweight people in cold climates than warm ones?
Now there are many other factors that matter more (diet & exercise) are the big ones. And the rise of the TV, computers, Pro Football (watching TV for hours), cars, fast food, medications, cubicles, and a bunch of other things became mainstream during the past 40 years as well. But I just thought of this out of the blue. I was a few months behind the researchers that came up with the idea first.