You will also die if you eat precisely the amount of calories you burn every day.

There exists something called a "feedback loop", something common in biology. You would probably find it interesting, you should look it up.

Basically, it means that if you try to chronically eat, say, 1% more calories than are burned, your body will try to burn more calories to compensate.

I'm not sure I grasp the rest of your comment, could you try again to explain? The wheat farm your ancestors worked did not provide the excess of cheap calories available to the present day American.