Experts in Bariatric and Metabolic Disorders

Bariatric surgery, and the lifestyle changes required to achieve your desired outcome, requires a serious commitment on your part. But your commitment also comes with a promise from the Bariatric and Metabolic Interdisciplinary Clinic (BMI Clinic) to do everything we can to help you succeed.  Stanford's Bariatric Surgery Clinic is first Center of Excellence in Northern California to achieve Level 1A certification by the American College of Surgeons.

Bariatric Surgery Clinic
900 Blake Wilbur Drive
Palo Alto, CA 94304
Phone: 650-736-5800 Getting Here
Maps & Directions
900 Blake Wilbur Drive
Palo Alto, CA 94304
Phone: 650-736-5800 Getting Here

Our Doctors

Care and Treatment of Bariatric and Metabolic Disorders

Frequently Asked Questions

Bariatric Surgery is a significant operation, not just as a procedure, but as a step toward changing the way you live. You should have questions. Here are some of the common ones we receive, and answers that should help. As always, if you’d like more information, feel free to contact us.

Is there an age restriction for the surgery?

Surgery is done on patients between the ages of 18 - 65. If you're younger than 18, please refer to our Adolescent Bariatric Surgery Program at Lucile Packard Children's Hospital. If you are older than 65, cases are evaluated on a case-by-case basis. Please keep in mind your insurance may restrict your options.

Is there a weight limit for this operation?

We look at Body Mass Index (BMI), which is the weight over the body surface area squared. Patients who have a BMI of 35-40 and have obesity related co-morbidities are candidates for this surgery. Patients who have a BMI greater than 40, even if they don't have co-morbidities, are also candidates for this operation.

What are obesity related co-morbidities?

These include diabetes, hypertension, arthritis, degenerative joint disease, sleep apnea, low pack pain, gastroesophageal reflux disease, stress incontinence, high cholesterol and triglyceride levels and depression.

How successful are these operations?

The gastric bypass operation allows you to lose up to 82% of your excess body weight, however it's almost 100% effective in reversing obesity related co-morbidities including sleep apnea, hypertension and diabetes. The adjustable gastric banding (lap-band) operation allows you to lose 50% of your excess body weight at two years. It's also effective in reversing obesity related co-morbidities. The sleeve gastrectomy is between the gastric bypass and gastric banding in terms of weight loss with 60% excess weight loss at one year.

What are the pre-operative requirements in order to undergo either operation?
  • You must have a stable relationship with a primary care physician who has been treating you continuously for one year prior to consideration for surgery.
  • You must have a dietician evaluation.
  • You must have a psychological evaluation. Patients with bipolar disease are generally excluded from consideration for surgery.
  • If you have a history of heart disease, if you've taken Fen-Phen in the past, if you're over the age of 50, or other cardiac risk factors, you'll require an echocardiogram.
  • At some point prior to surgery, you'll have to undergo a chest X-ray, an EKG and blood tests.
What does laparoscopic surgery mean?

Laparoscopic surgery means that instead of making one large incision in your abdomen, we make five small incisions in the middle and to the left side of your abdomen. These smaller incisions allow you to recover faster. You'll also experience less pain, leave the hospital sooner and will be back to your normal activity sooner. In general, we start all of our cases laparoscopically unless the patient has had previous surgery on their stomach.

Why is there a 10% pre-operative weight loss required?

We require patients to begin a diet and exercise program that allows them to lose 10% of their weight pre-operatively for three reasons:

  • Patients who undergo weight loss before surgery have fewer complications during and after surgery.
  • This allows patients to truly understand the lifestyle changes that will occur after surgery and therefore make an informed consent about the diet and exercise programs that they will have to be on for the rest of their lives.
  • This allows us to identify the patients who are truly motivated and therefore who will be most successful following surgery.
    Most important, we'll work with you to develop a weight-loss program to achieve the 10% reduction goal. 
When will I meet the surgeon?

Your initial workup/consult will be done by a surgeon who will screen you for medical problems. Once the surgeon has determined that you're a good candidate for this operation and if you've met all of our criteria, you'll then be given a plan for bariatric surgery.

When will my surgery be scheduled?

We will work with you to quickly get you started on you new life.

What are the risks of the operation?

Weight loss surgery is major abdominal surgery with significant risks. However, we know experience counts and high-volume centers like Stanford Health Care have an extremely low complications rate. The following potential complications include, but are not limited to:

  • Risk from general anesthesia
  • Bleeding
  • Infection
  • Pneumonia
  • Blood clot in the legs or lungs
  • Hernias (internally or externally)
  • Blockage or obstruction
  • Narrowing where surgeons suture the pouch to the intestine, which can require another endoscopy and dilation
  • Leakage from the stomach or the intestines
  • Injury to liver and/or spleen
  • Pulmonary and/or cardiac and/or renal failure

With the adjustable gastric band (lap-band), there's a risk that the band can either slip or erode. There's a risk that you will not lose weight if you don't follow the diet and exercise program. There's a risk of needing another operation or conversion to an open operation with a long incision. While there's a risk of death with each procedure: 1-in-200 with the gastric bypass, 1-in-500 with sleeve gastrectomy, and 1-in-10,000 with the lap band. 

What is the conversion rate?

Conversion to open surgery is required in less than 1% of patients. The risk of conversion is higher in patients who have had previous upper abdominal surgery.

How do I know which operation is for me?

Deciding which procedure is best for you is largely a personal one best achieved in discussion with your surgeon.

Is there anything else I need to know?

It's very important that you understand this surgery won't remove your sense of hunger. It won't cause you to lose your desire to eat and it won't remove any of the psychological cravings that you may have for food. If you eat when you're stressed, you'll still feel like eating when you're stressed. Therefore, it'll be very important that you understand the stresses that make you feel like eating and identify other ways of resolving these issues. Part of your Bariatric Surgery team can include a psychologist to help you understand your eating triggers and how to cope with them.

What will happen when I'm in the hospital?

In general, you'll be in the hospital for two nights. We'll expect you to get up and walk while you're in the hospital - this is your best defense against blood clots. You'll meet with the dietician before going home and while you're here, you'll have a clear liquid diet that will be limited to a medicine cup every 15 minutes.

Once home, you can drink until full. Please walk, drink once every hour, and take in at least 40 - 60 grams of protein daily for women, and 60 - 80 grams of protein daily for men. After returning home, if you have any medical concerns during business hours, please contact the RN at 650-736-7102.

If you need to contact someone after hours, holidays, or on weekends, please call 650-723-6661.


Clinical Trials

Clinical trials are research studies that evaluate a new medical approach, device, drug, or other treatment. As a Stanford Health Care patient, you have access to the latest, advanced clinical trials.

Open trials refer to studies currently accepting participants. Closed trials are not currently enrolling, but may open in the future.

For Patients

A referral from your primary care doctor is required.


Bariatric surgery requirements include:

  • Proof of six months supervised attempts at weight loss with documented weights
  • Psychological evaluation
  • Upper endoscopy
  • Meet with a nutritionist before and after surgery
  • Diagnostic tests completed within six months prior to surgery

Bring or mail ahead of time the results of your diagnostic tests, your completed Patient Questionnaire and Food Diary. You can also receive a copies of forms from our New Patient Coordinator at 650-736-7102.

Tip: We receive hundreds of faxes daily. Please send any information via overnight mail services so that you will have a tracking number and will allow us to securely receive your paperwork, labs and consultations.

International Patients
Phone: +1 650-723-8561

For Health Care Professionals


Phone: 1-866-742-4811
Fax: 650-320-9443
Monday – Friday, 8:30 a.m. – 5 p.m.

Stanford Health Care (formerly Stanford Hospital & Clinics) provides comprehensive services to refer and track patients, as well as provides the latest information and news for physicians and office staff. For help with all referral needs and questions visit Referring Physicians.


Fax a referral form with supporting documentation to 650-320-9443.

Track your patients' progress and communicate with Stanford providers securely online.

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