Weight Loss & Obesity Home

Frequently Asked Questions About Weight Loss Surgery

How does weight loss surgery work, and could it help you? Get answers here to frequently asked questions about weight loss surgery.

Should I Consider Having Weight Loss Surgery?

Weight loss surgery is not for everyone. Doctors generally recommend it only for people who:

In early 2011, the FDA approved the use of Lap-Band restrictive surgery in those with a BMI of 30 or higher who have at least one obesity-related condition, such as diabetes.

How Will Weight Loss Surgery Help Me Lose Weight?

There are two basic types of weight loss surgery -- restrictive surgeries and malabsorptive surgeries. Each helps with weight loss in different ways.

  • Restrictive surgeries (like adjustable gastric banding) work by physically restricting the stomach's size, limiting the amount of solid food you can eat. A normal stomach can hold about three pints of food. After weight loss surgery, a stomach may only hold one ounce of food, although over time it may be able to hold two or three ounces of food.
  • Malabsorptive surgeries (like gastric bypass) work by changing the way your digestive system absorbs food. This type of weight loss surgery is more complicated. The surgeon removes parts of your intestine, creating a shortcut for the food to be digested. This means that fewer calories get absorbed into the body. The combined malabsorptive/restrictive surgery also creates a smaller stomach pouch, which restricts the amount of food you can eat.

What Are the Pros and Cons of Various Weight Loss Surgeries?

Gastric Banding Surgery

The Pros:

  • Gastric banding is often a minimally invasive surgery performed with small incisions, a laparoscope (a tiny camera), and special instruments.
  • There is no need to cut into the stomach or intestine, and recovery is usually faster than with gastric bypass surgery.
  • The surgery can be reversed by surgically removing the band.
  • The band can be tightened or loosened in the doctor's office to control weight loss and nutritional needs. To tighten the band, saline solution is injected into the band. To loosen it, the liquid is removed with a needle.
  • Serious complications are uncommon. But gastric bands can slip out of place, become too loose, or leak. Should this occur, additional surgery may be necessary.


The Cons:

  • Your weight loss may be less dramatic than with gastric bypass. The average loss is 21% of your excess weight after one year, and 47% of your excess weight after two years.
  • You may regain some of the weight over the years. Ten years after surgery, the average weight loss is about 13%.

Gastric Bypass Surgery

The Pros:

  • Weight loss is quick and dramatic. People lose an average of 38% of their excess body weight in the first year, and 62% of excess body weight in two years.
  • Because weight loss is quick, weight-related health problems such as diabetes, high blood pressure, high cholesterol, arthritis, sleep apnea, and heartburn improve quickly.
  • Many people keep most of the weight off for 10 years or longer. After 10 years, the average weight loss is 25%.
  • Loss of stomach tissue results in a drop in the so-called "hunger hormone" Ghrelin, which helps control appetite.

The Cons:

  • Gastric bypass surgery is riskier and is associated with more complications. Although the surgery is generally safe, 10% of people have minor complications. Less than 5% have serious (potentially life-threatening) complications. The risk of death is under 1%.
  • The surgery may result in dumping syndrome, which occurs when food moves too quickly through the stomach and intestines. Dumping syndrome can cause shaking, sweating, dizziness, nausea, and severe diarrhea.
  • Gastric bypass is generally considered irreversible. The surgery permanently changes how your body digests food.

What Are Typical Risks After Weight Loss Surgery?

Typical risks associated with weight loss surgery include:

As with any surgery, wound infections can occur up to three weeks after surgery. These can be treated with antibiotics, and sometimes require further surgery.

Complications that may develop following weight loss surgery include:


Rare but serious complications include:

  • Bleeding in the stool, or black stools
  • Leaks in new connections made by weight loss surgery; these usually occur within five days of surgery.
  • Blood clots in the lungs, called pulmonary emboli, occur less than 1% of the time; they are the most common cause of death after weight loss surgery. Blood clots can be prevented with blood thinning medicines and frequent activity.
  • Blood clots in the legs, called deep vein thrombosis, or DVT
  • Pneumonia

How Much Weight Will I Lose After Surgery?

After gastric bypass surgery, people generally lose 61% of excess weight. One long-term follow-up study found that 25% of the excess weight remained off 10 years later.

After gastric banding, people lose on average 47% of their excess weight. About 13% of it remained off 10 years later, according to the long-term study.

How Does Weight Loss Surgery Affect Overall Health?

Obesity-related medical problems will generally improve after weight loss surgery. These include:

  • Obstructive sleep apnea
  • Type 2 diabetes
  • Gastroesophageal reflux disease (GERD)
  • High cholesterol
  • Degenerative joint disease or orthopedic problems
  • High blood pressure
  • Asthma
  • Urinary incontinence

How Does Weight Loss Surgery Affect Nutrition?

After weight loss surgery, the body has difficulty absorbing certain important nutrients, including:

  • Iron
  • Vitamin B-12
  • Folate
  • Calcium
  • Vitamin D

However, taking a daily multivitamin, plus other supplements, can prevent or reduce these deficiencies.

What Lifestyle Changes Are Necessary After Weight Loss Surgery?

Over time, some people regain weight despite bariatric surgery. Some eat high-calorie or high-fat foods instead of healthy foods -- and eat them too often. Some people rely on "soft meals" such as ice cream and milk shakes.

The body itself may change over time, too, leading to weight gain. The digestive tract might begin absorbing more calories. Even the size of your surgical stomach can expand gradually over time.

To keep the weight off, you need to work at it. Here are some tips:

  • Eat very small meals. Adapting to small meals is challenging but necessary. Eat small amounts of food slowly, chew well, and eat lots of protein.
  • Make nutrition a priority. You must make the foods you eat count. Good nutrition is critically important. You must also take the right supplements, as recommended by your health care provider, because serious malnutrition occurs easily following weight loss surgery. A dietitian can create a diet and nutrition plan designed to meet your needs.
  • Exercise regularly. Many obese people aren't used to exercise, but it's very important to prevent weight regain. The good news: Once you start losing weight, exercise will get easier.


How Will My Physical Appearance Change After Weight Loss Surgery?

As you start losing weight, you will likely be thrilled with your new appearance. However, many people who lose a lot of weight often find their skin looks loose and baggy. You may want plastic surgery to remove this excess skin.

Will My Social Life and Relationships Change After Weight Loss Surgery?

Your relationships with friends and family may indeed change after weight loss surgery. For many people, food and drink are the basis for socializing. After weight loss surgery, you must find other ways to socialize -- ways that aren't focused on food.

Also, as you lose weight, the results will be obvious. People will notice, and ask you about your appearance. Prepare for these questions ahead of time -- and consider how you want to answer them.

Will I Feel Like Myself After I Lose Weight?

Losing a significant amount of weight is no small matter. In fact, the effects are profound and far-reaching. Life may seem disconcerting at times. You may feel odd, not quite like yourself. You may feel overwhelmed by the lifestyle changes you must make for the rest of your life. You may have reached for food as comfort -- and have difficulty giving it up.

A therapist can help you get through this complicated period. A support group can also help. Ask your doctor about support groups for people who have had weight loss surgery. It helps to meet people who are making the same adjustments you're making -- and can help keep you on track with your weight loss program.

What Is the Cost of Weight Loss Surgery? Will Insurance Cover It?

A typical weight loss surgery can run from $20,000 to $35,000 -- so insurance coverage is critical for most people. Every insurance company is different, but before agreeing to cover the surgery, most insurance companies want documentation of the patient's struggle with obesity. They want a primary care doctor's records indicating that the patient has tried to lose weight through diet, exercise, and psychological counseling -- for at least five years. Also, medical causes of obesity must be ruled out. It pays to ensure that your doctor documents your efforts early on, so surgery is an option later.


How Do I Find a Bariatric Surgeon?

Clearly, you want a bariatric surgeon who is very experienced in this specialty area. Research shows that the more experienced the surgeon, the lower the risk of death or complications during or after the surgery.

To identify an excellent surgeon, collect a list of names. Ask friends and family members. Ask coworkers. You might be surprised -- lots of people often know others who have had weight loss surgery and want to share their doctor's name.

Check into centers and hospitals offering educational seminars for people considering weight loss surgery. You can learn more about the actual procedure, the benefits and the risks. You may also get names of specialists who perform these surgeries. Go to these seminars and ask questions.

Here are some questions to consider when choosing a bariatric surgeon:

  • Is the specialist board certified by the American Board of Surgery?
  • Is the specialist a member of the American Society of Bariatric Surgeons?
  • How many weight loss surgeries has the surgeon performed? (100 or more is ideal.)
  • How many of the surgeon’s patients have died from weight loss surgery? (Less than 1% is the average.)
  • How often do patients have complications? What side effects are most common?
  • What is the surgeon's success rate?

Don't rush into weight loss surgery. Most people take two years to think about it. Talk to family and friends. Talk to surgeons and to people at the hospital centers. Prepare yourself mentally and physically. Make sure you are committed to changing your lifestyle and to keeping the weight off forever.

WebMD Medical Reference Reviewed by Varnada Karriem-Norwood, MD on August 28, 2014


News release, Allergan.
Sjöström, L. New England Journal of Medicine, December 2004.
WebMD Medical Reference: "What to Expect After Weight Loss Surgery;" "Your Options in Weight Loss Surgery: Making the Choice;" "Preparing for Weight Loss Surgery;" "Life After Weight Loss Surgery;" and "Is Weight Loss Surgery for You?"

© 2014 WebMD, LLC. All rights reserved.