Problems that may occur following bariatric surgery and suggested dietary modifications are:

Nausea and vomiting

This is often encountered and may suggest either poor dietary compliance or a potential technical problem. If nausea and vomiting occur after eating a new food, wait several days before trying it again. It may be necessary to eat more liquid or pureed foods temporarily. Eating too fast, eating too much, or insufficient chewing may also cause nausea or vomiting. Rest your stomach for two to four hours and then try eating again. If the problem persists, contact your surgeon to rule out an ulcer or potential technical problem.

Dumping syndrome

Dumping syndrome occurs when the contents of the stomach empty too quickly into the small intestine, causing nausea, cramping, diarrhea, sweating, faintness, and palpitations. Try solid meals, low in simple sugars but high in complex carbohydrates. Try to avoid simple sugars. Check lactose tolerance.

Pain in shoulder or upper chest area

Stop eating if pain occurs during eating and try to eat later after the pain has resolved.


This may occur with inadequate fluid intake or with persistent nausea, vomiting, or diarrhea. At least six cups of fluids daily are recommended.

Lactose intolerance

Use lactose-treated milk and lactase enzyme tablets.


This may occur temporarily during the first postoperative month but generally resolves with adaptation to changes in the volume of food. Consuming fruits and juices regularly usually reduces the risk of recurring constipation.


Limit ingestion of high-fiber foods, greasy foods, milk and milk products, and very hot or cold foods. Eat small frequent meals. Drink plenty of fluids.

Blockage of the stoma with gastric bypass

The stoma (connection) may be temporarily blocked if foods with large particles are eaten without thoroughly chewing. If symptoms of pain, nausea, and vomiting persist, a physician should be contacted.

When to contact your surgeon following bariatric surgery

If any of the above problems persist for more than a few days, please contact your surgeon immediately.


Source: This article originally appeared on the University of Iowa Hospitals & Clinics website. It was first published in June, 2018.