Come on, we bet you have a theory. Everyone has one. So take a look at the New Yorker magazine and see how yours mesh with the ones outlined in an article by Elizabeth Kolbert. (No great revelations, but it's a good read.)
In the intro, Kolbert outlines the facts -- an abrupt increase in the weight of Americans in the 1980s, when the number of people classified as overweight jumped to 33% from 25%, after decades of not much change. Since then, we've gotten still fatter.
Theories abound. In fact, she writes, "what might be called weight-gain books, which attempt to account for our corpulence, are an expanding genre." She reviews a few of them, including:
"The Evolution of Obesity" by Michael L. Power and Jay Schulkin argues that we're fat because the environment we live in is out of sync with the one our species evolved in. Calories are everywhere, now, where once they were hard to come by. Thus, we are designed to desire to consume and to resist calorie loss.
"The Fattening of America" by Eric Finkelstein with Laurie Zuckerman argues that we fattened up in the 1980s because food got really cheap then -- and we humans love a bargain.
"The End of Overeating" by David Kessler says the reason we're plumping up is because the food industry has expended a lot of effort in making packaged foods taste really, really good as well as very, very fattening.
And check out the follow-up article in which Kolbert answers questions from readers.
If you want a review of various other why-we-got-fat theories (some a lot more credible than others), read these short articles by Karen Ravn, written for the L.A. Times Health section, examining high-fructose corn syrup, a virus, low-fat foods, lack of sleep, smoking cessation, too much stress, to name a few.
-- Rosie Mestel
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