I have heard many discuss the need to eat 5 meals a day to lose weight and boost metabolism.
Do what works for your body but I do not think this is necessary for everyone. I also think there can be more than one way to achieve the results you are looking for. What is more important to me is what you are eating, how much you move (exercise), and how well you are eliminating when you go to the bathroom.
If you eat a sandwich made with gluten-filled bread, nitrite-filled ham, cheese from a cow fed gmo corn and soy and filled with steroids, mayonnaise made with eggs from chickens who never get outside and are pumped with steroids to where they are growing so fast their legs can't hold them up...there are probably factors within the food you are eating that are promoting weight retention.
Now lets compare that to eating a chicken thigh from a free-range chicken, 1/2-1 sweet potato, and 1 cup of cooked swiss chard. Do you see the difference?
One body part I always recommend exercising regularly is your abs. These muscles are right over your digestive track. If you start regularly working out your abs, you will more than likely see a change in your metabolism, and a change in the amount of belly fat. Muscles burn fat, so why not exercise the ones right next to the belly fat. If you've never been pushed in the area of ab workouts before, I highly encourage getting an ab workout video, working with a personal trainer, or joining a workout group.
I like to hear that clients are eliminating at least once per day. If you are only going a 1-2 times per week or less, work on increasing the frequency. You can do this by increasing your water and fiber intake, cardio exercise, and decrease constipating foods like white bread and other junk food.