[throwawayboise]

Yes. People and jobs are more sedentary. Kids sit in front of screens instead of riding bikes to the park and playing ball or just running around. Fat in prepared foods has been reduced, replaced with corn syrup. Portion sizes for food and drink at restaurants have probably close to doubled since the 1970s.

We are less active and we're eating more. Thus we got fat.

[higgsbozo]

Exactly. Fats were deemed the enemy #1 and the problem with corn syrup has relatively only recently been brought to public's attention. A friend of mine from Europe spent the summer in Florida riding bike all day long under a swelling sun, selling encyclopedias. He should have lost weight, but he came back with puffy cheeks and belly. I blame corn syrup for that :)

[meowzero]

Not corn syrup. He probably ate well while he was vacationing in Europe. Exercise doesn't really burn as much calories as people think.

I did similar things where I probably had 10k steps a day in Europe because we walked everywhere all the time. We also ate a lot and often. So my weight didn't change. Heck, I thinks some people gained.