To put dumping syndrome in simple terms, it occurs when the stomach empties very quickly and the small intestine fills quickly. Dumping syndrome can occur after gastric sleeve surgery or gastric bypass surgery. Also, it may occur in consequence of damaging the vagus nerve.

The dumping syndrome is mainly triggered by food intake. There are two dumping syndrome in terms of early and late.

Early dumping syndrome occurs in response to the rapid passage of nutrients into the small intestine.

Symptoms of early dumping syndrome

  • Gastrointestinal
    • stomach pain
    • diarrhea
    • abdominal sounds
    • flatulence
    • nausea
  • Vasomotor
    • redness
    • sweating
    • palpitation
    • hypotension (low blood pressure)
    • fainting

Late dumping syndrome occurs between 1 and 3 hours after eating. Rapid gastric emptying leads to a high concentration of glucose in the intestine. Rapidly absorbed glucose (sugar) from the intestinal lumen causes an increase in blood sugar and in insulin secretion by the pancreas. Hypoglycemia can occur due to the absorption of blood sugar by the cells and the decrease in the initial increase in glycemia.

Symptoms of late dumping syndrome

  • Hypoglycemia
    • sweating
    • palpitation
    • hunger
    • weakness
    • tremor
    • fainting

The dumping syndrome is seen less in people who have gastric sleeve surgery than in people who have metabolic surgery. According to the researches, after bariatric surgery, 40% of patients have experienced this syndrome at least once or more.

Dumping syndrome is mostly improved if you regulate your diet. You can prevent dumping syndrome as follows:

  • Avoid simple carbohydrates and refined sugars
  • Do not get solid and liquid food at the same time
  • Choose lukewarm food instead of very cold and warm food
  • Chew your food abundantly and don't forget to wait between bites a while
  • Avoid to eat your food fast


Tack J, Arts J, Caenepeel P, DeWulf D, Bisschops R. Pathophysiology, Diagnosis and management of postoperative dumping syndrome, Nat Rev Gastroenterol Hepatol 2009 Oct;6(10):583e90.

Arts J, Caenepeel P, Bisschops R, Dewulf D, Holvoet L, Piessevaux H, et al. Efficacy of the long-acting repeatable formulation of the somatostatin analogue octreotide in postoperative dumping, Clin Gastroenterol Hepatol 2009 Apr;7(4):432e7.

Jan Tack, M.D., Ph.D., Professor of Medicine, Eveline Deloose, Complications of bariatric surgery: Dumping syndrome, reflux and vitamin deficiencies, Best Practice & Research Clinical Gastroenterology 28 (2014) 741e749