What foods stay in the stomach region?

As a general rule of thumb, white foods are usually processed. You want to stay away from these.

For example, pancake mixes, biscuits, sour dough bread, rice cakes, fat free or low fat cakes, snacks, chips, baked potatoes, donuts etc.

Why?
Your liver converts these foods into triglycerides, which leads to fat stores. These fat stores can hang around in the gut of your stomach region for a long period of time.