Rehman Bhai ... yes, the tummy can be controlled but it needs lot more than intention, commitment, patience and exercise.
Fat cells are very very intelligent cells. Once they are formed, they never go away. If you start dieting or start exercising, they sense danger for their survival and slow down their metabolic rate .. become inactive and shrink in size. Once the person starts eating normally, they act very aggressive, and draw nutrition from adjoining muscle cells and grow bigger in size than before.
This kind of "intelligent" behaviour of fat cells is somewhat like what we see in cancer cells .. they survive at the cost of destruction of normal and healthy cells.
I can cite an example. More people have heart attacks during and after losing weight than ordinary happy overweight people ... It cause when you start dieting, the intelligent fat cells survive, while the not-so-intelligent muscle cells die due to starvation ... death of heart muscle cells proves fatal.