Hi Bhavana,
I really doubt that belly fat reduction have to do anything with oil massage. If so then all would have opt for oil massage. Tummy reduction is really a tough job and have to do some exercises along with the healthy food. Again, the exercise regime to reduce tummy fat depends on your body fat percentage. If your body fat percentage is high then its better that you do more of cardio training exercises and less of weight training exercises for tummy and if your body fat percentage is in normal range then its better that you do more of weight training exercises for tummy and less of cardio training exercises. So, the two exercises has to be balanced according to your body fat percentage. Also, keep a control on your daily diet and avoid any junk or oily food.