What Causes Abdominal Distention Along With Flatulence And Excessive Burping?

HI I m 53 year old working (moderate) woman . suffering from migraine (pitt) for 25 years .however for 5 -7years its frequency is gradually reducing . main problem is very thin limbs and very fat belly .frequent Farts and burps . live in stress because of unavoidable circumstances . any diet control , exercise or walk results in thinner limbs . no effect on belly fat .