Gastric BypassGastric bypass, also called Roux-en-Y (roo-en-wy) gastric bypass, is a type of weight-loss surgery that involves creating a small pouch from the stomach and connecting the newly created pouch directly to the small intestine. After gastric bypass, swallowed food will go into this small pouch of stomach and then directly into the small intestine, thereby bypassing most of your stomach and the first section of your small intestine.

Gastric bypass is one of the most common types of bariatric surgery in the United States. Gastric bypass is done when diet and exercise haven’t worked or when you have serious health problems because of your weight.


Why it’s done

Gastric bypass is done to help you lose excess weight and reduce your risk of potentially life-threatening weight-related health problems, including:

Gastroesophageal reflux disease

Heart disease

High blood pressure

High cholesterol

Obstructive sleep apnea

Type 2 diabetes




Gastric bypass is typically done only after you’ve tried to lose weight by improving your diet and exercise habits.


Who it’s for

In general, gastric bypass and other weight-loss surgeries could be an option for you if:

Your body mass index (BMI) is 40 or higher (extreme obesity).

Your BMI is 35 to 39.9 (obesity), and you have a serious weight-related health problem, such as type 2 diabetes, high blood pressure or severe sleep apnea. In some cases, you may qualify for certain types of weight-loss surgery if your BMI is 30 to 34 and you have serious weight-related health problems.


But gastric bypass isn’t for everyone who is severely overweight. You may need to meet certain medical guidelines to qualify for weight-loss surgery. You likely will have an extensive screening process to see if you qualify.

You must also be willing to make permanent changes to lead a healthier lifestyle. You may be required to participate in long-term follow-up plans that include monitoring your nutrition, your lifestyle and behavior, and your medical conditions.

Check with your health insurance plan or your regional Medicare or Medicaid office to find out if your policy covers weight-loss surgery.



As with any major surgery, gastric bypass and other weight-loss surgeries pose potential health risks, both in the short term and long term.

Risks associated with the surgical procedure are similar to any abdominal surgery and can include:

Excessive bleeding


Adverse reactions to anesthesia

Blood clots

Lung or breathing problems

Leaks in your gastrointestinal system


Longer term risks and complications of gastric bypass can include:

Bowel obstruction

Dumping syndrome, causing diarrhea, nausea or vomiting



Low blood sugar (hypoglycemia)


Stomach perforation




Rarely, complications of gastric bypass can be fatal.


What qualifies you for gastric bypass surgery?

Guidelines to qualify for gastric bypass surgery

Efforts to lose weight with diet and exercise have been unsuccessful.

Your body mass index (BMI) is 40 or higher.

Your BMI is 35 or more and you have a serious weight-related health problem, such as type 2 diabetes, high blood pressure or severe sleep apnea.


What foods can you not eat after gastric bypass surgery?

Soft foods

Ground lean meat or poultry.

Flaked fish.


Cottage cheese.

Cooked or dried cereal.


Canned or soft fresh fruit, without seeds or skin.

Cooked vegetables, without skin.


How long does food stay in your stomach after gastric bypass?

Dumping syndrome after gastric bypass surgery is when food gets “dumped” directly from your stomach pouch into your small intestine without being digested. There are 2 types of dumping syndrome: early and late. Early dumping happens 10 to 30 minutes after a meal. Late dumping happens 1 to 3 hours after eating.


What happens to the rest of the stomach after gastric bypass?

After gastric bypass surgery, the rest of the stomach remains in the body. The blood vessels that supply blood to the stomach remain intact. … Also, the stomach has more functions than just food store. The stomach makes gastric acid and juices.


Disadvantages of Gastric Bypass

Permanent change in your anatomy.

Restricts dietary choice for the rest of your life.

Dumping syndrome from eating foods high in sugar, calories and fat causes discomfort, 20-30 minutes of nausea, and possibly vomiting, diarrhea, and overall weakness each time.