There is no delicate way to put it. Americans are fat and getting fatter every year.
presently, 38% of men and 41% of women are obese, numbers that have doubled over the past three decades, and worse.
The simple explanation is that we eat more calories than we burn each day, leading to an excess of calories in the body that are converted to fat and stored.
The fast-food industry also was hard at work contributing to American fatness. First was the introduction of "value meals," which combined sugary soft drinks with high-fat French fries and burgers.
Soft drinks cause a big insulin response while fries and burgers provide lots of dietary fat calories. Insulin not only regulates blood sugar, but it also promotes the conversion of excess calories into body fat.
At the same time, busy Americans had less time to cook wholesome meals at home, and the frequency of eating out doubled in recent years.
On the contrary, we evolved from early man when eating was unpredictable, and that fact combined with our drive to survive has shaped our behavior in a number of ways, starting with hunger, our strongest drive.
we are denied food for a prolonged period, the hunger drive is so strong we will do almost anything to assuage it.
we consume too many calories, our bodies are programmed to take the excess energy and store it in the form of body fat. you can't eat for a while, a common occurrence for our ancestors, you can simply tap into the energy you have stored as fat.