At the risk of sounding like a conspiracy nut, I would say it goes a step farther. It's very profitable to stuff us all full of processed shit and keep us fat and sick. In developing countries there is no such thing as high cholesterol, diabetes, heart disease, etc. In our culture it seems like every person has some type of food borne ailment, and there is a pill to treat the symptoms of each and every one of these ailments.
Food/pharmaceuticals/health care are all intertwined, and are VERY big business. How much money would be lost if we all ate right, exercised, and were the models of health?