[ssutch3]

The type of food we eat has a major impact on the prevalence of overweight individuals. The fast/easy food is the most calorie dense, most affordable, and least satiating compared to the food we used to eat 40+ years ago. Even adjusting for eating habits and lifestyle differences (sedentary people tend to get bored and snack) the food itself is just more efficient at delivering calories than it used to be and our population hasn't adjusted to this fact.

[DoreenMichele]

Given how desperately most people want to be thin and beautiful, if our standard answer of "calories in and calories burned" as our sum total understanding of how weight gain works were accurate, I imagine we wouldn't be seeing stats like "nearly three fourths of Americans are overweight."