HIGH COLORIE DIET IS WHY PEOPLE ARE FAT !!!
-HIGH CARB DIET IN CALORIC DEFICIT MAKE LEAN !!!
-HIGH PROTEIN DIET IN CALORIC DEFICIT MAKE LEAN !!!
-HIGH FAT DIET IN CALORIC DEFICIT MAKE YOU LEAN !!!
I HAD TO BREAK IT DOWN FOR THE RETARDS OF THIS BOARD !!! 
What do you think the percentage of people who actually do a HIGH CARB DIET IN CALORIC DEFICIT? In the west it has to be under 1% of the people. And if people gain weight in a High Protein or a high fat diet with low to no carbs, type II diabetes isn't a problem. However, if someone is adding body weight in a high carb/sugar diet(over the age of 40)and has so for years, type II comes into effect.
However, your original post I agree with. In a caloric deficit state most people won't have of the problems were discussing regardless of their diet...