No exercise will allow you to spot reduce fat from specific areas of your body. To lose belly fat, you need to lose fat from your body overall. To do this, you need to burn more calories than you consume. Adding exercise, like belly dancing, to your routine will increase your calorie burn and help you lose fat from your entire body, including your belly. To lose a single pound of fat, you'll need to burn an extra 3,500 calories over time.
A 130-pound person burns 207 calories belly dancing for 60 minutes. At this rate you would need to do belly dancing workouts adding up to 17 hours to lose 1 pound. If you weigh 160 pounds, you will burn about 254 calories per hour belly dancing. This would mean dancing for about 14 hours to lose a pound. At 190 pounds, you would burn 303 calories an hour, taking you about 11 1/2 hours to shed 1 pound of fat.