Leading the field in weight loss surgery

Gastric Bypass

Whole Health Weight Loss conveniently serves the San Francisco Bay Area

The gastric bypass is a weight loss procedure that involves reducing the size of the stomach and redirecting the flow of food into the lower small intestine, effectively bypassing a significant portion of the gastrointestinal tract.

These changes in anatomy have two important effects: the reduction in stomach size allows patients to experience significant restriction during meals, while the intestinal bypass reduces the absorption of calories from food.

Gastric bypass procedures such as Roux-en-Y gastric bypass fall into the larger category of massive weight loss surgery. There are a number of options of massive weight loss surgery that can provide dramatic results and help individuals treat obesity and reduce their weight significantly.

Please see the video below for a detailed illustration of the procedure.

roux en-y

What is a gastric bypass?

The oldest procedure often referred to as the “gold standard” of weight loss surgery, is the Roux-en-Y gastric bypass. In this procedure, the forty ounce stomach is reduced to a 1 – 2 ounce pouch using a stapling device. The small intestine is then cut and re-connected to the small stomach pouch to restore bowel continuity. The remaining 38 ounces of stomach and early part of the small intestine are bypassed resulting in decreased absorption of calories. Patients will, therefore, lose weight by the two mechanisms: restriction and malabsorption. 

We expect a 75% excess body weight loss within 1 year of the gastric bypass. This means that if you have 100 lbs to lose, you will lose 75 lbs in 1 year. These durable and dramatic results can only be achieved with weight loss surgery, the only known method for sustained weight loss on this scale. There are several different procedures available to the weight loss patient.

The Roux-en-Y Gastric Bypass is a surgical weight loss procedure that involves both restriction and malabsorption. A 1 – 2 ounce pouch of the stomach is separated from the remaining portion of the stomach using a stapling device. The lower part of the small intestine is then cut and connected to the 1 oz stomach pouch in order to re-establish bowel continuity.

The majority of the stomach is therefore bypassed and food passes directly from the small pouch into the small intestine. Since there is no bile entering the small intestine to mix with the food until further along the intestinal tract, there are profound effects on food absorption. Specifically, fat is poorly absorbed and as a consequence, patients lose a significant amount of weight.

What are the benefits of a gastric bypass?

The Roux-en-Y Gastric Bypass is a very effective weight loss surgery with an expectation of approximately 75% excess body weight loss at 1-year post-surgery.

In addition to weight loss, the gastric bypass offers strong metabolic effects that will result in control of blood sugar in diabetic patients.

Indeed, the cure rate for diabetes can be as high as 90% in certain groups of patients. Other medical problems associated with the metabolic syndrome (i.e. high blood pressure, elevated cholesterol and elevated triglycerides) are often resolved as well. Obstructive sleep apnea and arthritis may also be resolved or better controlled with this operation. The benefits of the gastric bypass are durable and profound.

Who is eligible for gastric bypass surgery?

As with all weight loss surgery, patients qualify for the Roux-en-Y gastric bypass based on the 1991 NIH consensus conference criteria. Patients with a body mass index (BMI) greater than 35 with one or more weight-related medical problem and those with a BMI of 40 or greater (click here to calculate your BMI), will qualify for surgery. Your surgeon will help you decide whether the gastric bypass is best suited to you during your consultation and on completion of your workup.

BMI calculator

You can calculate your BMI using the BMI calculator on our site. 

Dr. Scott Perryman

Dr. Scott Perryman has a passion for providing patients with treatments that provide direct, profound and impactful results. As a top-rated expert in minimally-invasive and weight loss surgery, Dr. Perryman combines personalized surgical care with a mindful approach to dramatic weight loss. Treatments provided by the Whole Health Institute are comprehensive and cover the pre-op and post-op experiences of the patient.

What is the gastric bypass procedure like?

This procedure is performed under general anesthesia, meaning patients are sleeping comfortably while the treatment is underway. The procedure is typically performed laparoscopically, which means small incisions are made to insert specialized instruments. Laparoscopy surgical techniques provide smaller scars, shorter recovery periods and minimal discomfort for the patient. More traditional surgical methods for intestinal surgery can double the amount of recovery duration and lengthen hospital time, adding to the cost of surgery. From start to finish, the procedure may be completed in about 2 hours.

The main phases of Roux-en-Y gastric bypass are:

  1. Anesthesia
  2. Initial laparoscopic incision
  3. Laparoscopic stapling is used to divide the upper section of the stomach from the small intestine.
  4. The end of the small intestine, called the Roux limb, is connected to the newly-created stomach pouch.
  5. The incisions are closed with sutures

What are the risks of a gastric bypass?

The Roux en Y gastric bypass is an ulcerogenic operation, meaning all patients are prone to ulcers post surgery. This risk will continue lifelong. Smoking cigarettes will turn a relatively low-risk possibility of developing ulcers into a relatively high risk of developing one. Patients must, therefore, quit smoking at least 6 weeks prior to surgery.

Patients who undergo the gastric bypass will have a lifelong risk of internal hernias. In this condition, a space created during the initial procedure allows small intestine to get trapped within it. Internal hernias occur rarely (~1%) and typically need operative resolution with a weight loss surgeon. The overall risk of complications with the gastric bypass is ~7% while the risks of death is <1%. Patients can expect to stay in the hospital for 2-3 days.

Patients often worry about the potential side-effects or complications of the gastric bypass.

Both the short (first 30 days after surgery) and long-term (lifelong) risks of this procedure are greater than those of the vertical sleeve gastrectomy, adjustable gastric band or intragastric balloon. Complications may include bleeding (short-term risk) leaks from the staple lines or at the intestinal connections (short-term risk), internal hernias (short and long-term risk), ulcers (short and long-term risk), dumping syndrome, malnutrition, micronutrient and vitamin deficiencies (short and long-term risks). Dumping syndrome is unique to the gastric bypass.

If patients eat a concentrated sweet food, it will cause a significant rapid rise in blood insulin to handle the absorption of alcohol. As the insulin rises rapidly, the blood sugar will drop precipitously and this leads the patient to experience symptoms of light-headedness, nausea, palpitations, sweating, and diarrhea or “dumping.” Dumping syndrome can, therefore, be a useful problem to have as it discourages poor food choices.

Micronutrients such as calcium and iron will be replaced on a continuing basis to avoid any deficiencies, as will your other vitamins.

What is recovery from a gastric bypass like?

Patients will spend 2-3 nights in the hospital and should, on average, need to take 1-2 weeks off of work. If you have a physical job requiring heavy labor, you may need as many as 6 weeks off of work following surgery. Since these surgeries are performed laparoscopically (with small incisions), you should only need pain medications for 3-5 days after surgery.

As soon as the patient begins their recovery, the surgical team will advise them on self-care practices. Patients must keep in mind that their digestive system has undergone a significant change that will require them to pay special attention to their nutritional intake.

In many cases, patients may need to:

  • Supplement with daily multivitamins by as much as 200%.
  • Pay special attention to their intake of calcium, B-12, vitamin D and iron. Patients may be required to increase their intake of these nutrients. B-12 and nutrients are available by oral supplements or injection. Due to the reduction in nutritional uptake, patients are often prescribed additional iron supplementation of 50 to 100 mg to prevent anemia.
  • A bi-annual blood test is advised to monitor for nutritional deficiency.

What are typical results of the gastric bypass?

There are other dramatic effects of this surgery. Type 2 diabetes will be resolved in 80-90% of patients and this effect is often observed within the first-week post-surgery. Bypassing the stomach and early small intestine means avoiding contact with the pancreas and changes in the release of sugar-regulating hormones such as GLP-1 and insulin.

Patients’ blood glucose and insulin levels are quickly improved, resulting in being able to discontinue diabetes medications soon after surgery.

What is the cost of a gastric bypass?

The cost of gastric bypass at the Whole Health Weight Loss Institute will vary from patient to patient. Every procedure is tailored to the specific goals and body of the individual to ensure the appropriate treatments and ideal results. If deemed medically necessary, the patient’s insurer may cover some of the cost of treatment.

At the end of the consultation, our staff works with each patient to determine the best treatment and payment plan.


Will I definitely lose weight from gastric bypass?

While each individual’s body is different, the large majority of patients who choose this procedure can expect to see at least 50 to 100% of loss of excess weight and a significant reduction in obesity-related health issues. At least half of patients are able to maintain their weight loss after five years with some degree of weight gain within two to five years.

Who can get gastric bypass?

This procedure is recommended for individuals who are at least 100 pounds over their ideal body weight.

Is gastric bypass safe?

Gastric bypass is a serious surgical procedure but is performed with an excellent safety record and proven results in the hands of trained, experienced specialists such as Dr. Perryman.

Can gastric bypass be reversed?

Yes. Gastric bypass can be reversed, but your intestinal function will not be the same as it was before the procedure.

Napa, CA Office

1300 Main St #200
Napa, CA 94559

napa weight loss office
Translate »