When nobody is watching try doing pelvic gyrations. If you take a moment to observe it you will see that it is the mid section of our body that gets the least bit of exercise and that is probably why the signs of weight gain are mostly seen there.
It is the same reason why we find it very difficult to lose weight in that section. So the best thing that you can do is consciously try to give that part a little bit of exercise.Stomach crunches might be too strenuous an exercise to start off with but gyrations are relatively mild. Pelvic gyrations make you thrust your midsection towards all directions and this is the best way of tightening every muscle in that mid section and that is of course what weight loss is all about.