Genetically modified foods are infused with chemicals that cause uncontrollable reactions through our nervous system. Our bodies are controlled by neurons, which send electro-chemical signals that trigger our involuntary system. This section of our brain is known as the reward center, which transcibes feelings of gradification. The chemicals in these foods cause neurons to gain an impulse of satisfaction in our reward center.  In "The End of Overeating" by David Kessler, he provides information of a study in where the consumption of sugar and fats combined provides an experience, which also stimulates the same neurons in our brains. The reaction from these foods lead for cravings that will satisfy the same experience that was initially obtained.