My mother, Age-67, is suffering from recurring stomach ache since last 5 years. Blood Tests, Stool tests & Upper GI tract endoscopy has not yielded any clue. She has regular motions ( i.e. no constipation or loose motion usually associated with IBS). Her diet includes Rice, Chapati (Whole wheat flour), Milk, Fruits, Vegetables and Fish- (No meat or eggs). What could be the reason for these stomach aches ( whole stomach ) which continues for weeks once it starts.