Gastric Bypass Dumping Types and Prevention

dumping syndrome
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If you've had weight loss surgery, your doctor may have warned you about gastric bypass dumping syndrome. Maybe you've had symptoms of dumping syndrome and didn't know what to do. Your best resource for help with any complications after surgery is always your doctor. But these basic facts will help you to understand, treat and prevent dumping syndrome.

What Is Dumping Syndrome?

Dumping syndrome is a problem that occurs in some patients after having weight loss surgery that reduces the size of the stomach. It is the result of food passing too quickly into the small intestine. It often happens when a patient eats certain foods, such as sweets or certain carbohydrate sources such as simple carbohydrates like sugar and some starches). It can also occur as a result of eating too much food at one time.

Experts don't know exactly why dumping occurs. Some researchers believe that the condition is caused by the rapid change in the size of the stomach. The prevalence of dumping syndrome in people who have had gastric bypass surgery can be as high as 24.3%.

As you might expect, gastric bypass dumping syndrome is uncomfortable and can be embarrassing. For that reason, it's important to communicate with your bariatric surgeon before your procedure to learn how to prevent the condition. You may be able to practice portion control and other healthy eating habits to prevent dumping even before you have your procedure performed.


There are two different kinds of dumping syndrome and each has a different set of symptoms. If you experience dumping syndrome symptoms, take note of the timing of the onset. The information may be helpful to your doctor as you try to prevent the condition from continuing.

Early dumping syndrome is more common than late dumping syndrome and occurs shortly after eating. Early gastric bypass dumping syndrome usually occurs within the first 10 to 30 minutes after a meal. According to the National Institutes of Health, symptoms of early dumping syndrome include:

  • Nausea
  • Vomiting
  • Abdominal pain and cramping
  • Diarrhea
  • Feeling uncomfortably full or bloated after a meal
  • Sweating
  • Weakness
  • Dizziness
  • Flushing, or blushing of the face or skin
  • Rapid or irregular heartbeat

Late dumping syndrome occurs two to three hours after you eat a meal. Symptoms of late dumping syndrome may include:

  • Hypoglycemia
  • Sweating
  • Weakness
  • Rapid or irregular heartbeat
  • Flushing
  • Dizziness


Talk to your weight loss doctor if you think you are experiencing gastric bypass dumping syndrome. There are medical tests used to diagnose dumping syndrome and medical treatments that may help you to manage and prevent the symptoms. Many times your doctor will suggest that you change your diet to reduce the chances that the syndrome will continue. 

To prevent dumping syndrome, medical experts generally recommend that you:

  • Avoid drinking liquids until 30 minutes after your meal
  • Avoid large meals and reduce portion sizes during meals
  • Eat more protein, complex carbohydrates like whole grains and fiber to feel full
  • Avoid simple carbohydrates like candy, table sugar, sweetened sodas, and juice drinks

The medical experts at The University of Rochester Medical Center also recommend laying down for 30 minutes after your meal to prevent or treat symptoms of dumping.

Edited by Malia Frey, Weight Loss Expert

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Article Sources
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  3. National Institute of Diabetes and Digestive and Kidney Diseases. Symptoms & Causes of Dumping Syndrome. Updated January 2019.

  4. Cleveland Clinic. Dumping Syndrome: Prevention. Updated April 24, 2018.

  5. University of Rochester Medical Center. Health Encyclopedia. Dumping syndrome after gastric bypass surgery. Updated 2020.