Dang, hubricide. When you try to be wrong, you really get the gold medal!
Every person has a different Basal Metabolic Rate. People with certain metabolic conditions (Type 1 Diabetes, PCOS, Syndrome X, Hyper- and Hypothyroid, etc.) utilize foods very differently than the normal person. If you are interested in doing any research, go look at Wikipedia to start you off. Then go hit real medical sites and have your mind blown!
Some people have a higher propensity towards obesity based on genetics. (Hey, just like some people have a higher propensity for getting a certain disease.)
Yes, there is a big issue in this society due to obesity. There is a great deal we do not know about the body. Have you ever wondered why if it is so easy to lose weight, we have so many overweight people? You'd think with all the medical knowledge at our fingertips, everyone would be the perfect weight. But we're not. If losing weight were easy and foolproof, there wouldn't be a zillion different diets out there. We'd have the One True Way and everyone would look like models.
BTW - it's not just Americans getting bigger. Rates of obesity are raising around the world.
Gah - I've got to go chase a toddler who has the right to think in such a child-like manner. Enough time has been spent on you.
Beauty is truth; truth beauty - that is all ye need to know on earth...except TCP/IP.