One of my latest articles on lowcarb.bellaonline.com talks about how obesity has become less deadly over the years. Back 200 years ago, if you were obese, you'd probably die relatively soon. One of the associated dangers would get to you rather quickly.
Now, for the first time in a long time, the average cholesterol in the US is under 200 - and it's not because we're thin. It's because drugs have meant that no matter what our weight, we can have relatively low cholesterol. There's no longer a real cholesterol danger even if we become quite heavy. There are many diabetes management drugs.
So imagine you were living 200 years ago. If you got heavy, you might work very hard to lose the weight, because you knew the risk of death was fairly serious. But in modern times, there's less incentive. Why trouble yourself with exercise? Why deny yourself the chocolate cake and ice cream? It's not that bad, really, to gain another 10 pounds.
What do you think of the medical improvements? Do you think you'd be more likely to exercise and to eat only healthy foods if there was harsher penalties from nature for being overweight?
I know someone who went from 300 to 220 in only a few months doing low carb and exercise - so it definitely was possible. But now he is back around 280 because he keeps eating pizza, lasagna, and rarely exercising. He watches TV and plays computer games. So he *could* lose the weight but he has little incentive to do it.