Carbonated beverages are discouraged because they may cause gas to be trapped in the anastomoses where the stomach pouch meets the small intestine. This gas not only creates discomfort but could also stretch the connection and, therefore, cause decreased feeling of fullness which will affect weight loss after the RYGB surgery.
Dumping syndrome is mainly a concern for RYGB patients who do not have a pyloric sphincter to regulate high-sugar foods that create a hypertonic response in the jejunum. As early as 10-13 minutes after eating the high-sugar food, the patient can get abdominal cramps and diarrhea or a feeling of dizziness and lightheadedness [4,5].
The dumping syndrome response to hyperosmolar meals is a problem in bariatric surgery patients because the pyloric sphincter would normally control the rate of flow from the stomach into the duodenum. After RYGB, the hypertonic gastric contents can rush into the small intestine after eating. Early symptoms can occur within minutes due to large fluid shift from blood plasma to the intestines and the increase in peristaltic activity of the gut. Several hours later symptoms of hypoglycemia may occur because of the high-blood-glucose spike and excessive insulin response .
Limiting the quantity of food and carbohydrate levels can minimize or prevent dumping syndrome. Fluids are restricted during meals and sugars—including lactose—are restricted or limited to control symptoms. Eating slowly and chewing thoroughly while sitting upright can also help reduce symptoms .