Weight Loss Surgery

How Surgery Reduces Weight
Am I a Candidate for Weight Loss Surgery?
Is Weight Loss Surgery for You?
Types of Weight Loss Surgeries

Vertical Sleeve Gastrectomy
Vertical Banded Gastroplasty
Roux-en-Y Gastric Bypass
Duodenal Switch
Biliopancreatic Diversion

 How Weight Loss Surgery Reduces Weight?
Gastrointestinal surgery for obesity, also called bariatric surgery, alters the digestive process so as to achieve rapid weight loss. The operations can be divided into three types: restrictive, malabsorptive, and combined restrictive/malabsorptive. Restrictive weight loss surgeries limit food intake by creating a narrow passage from the upper part of the stomach into the larger lower part, reducing the amount of food the stomach can hold and slowing the passage of food through the stomach. Malabsorptive weight loss surgeries do not limit food intake, but instead exclude most of the small intestine from the digestive tract so fewer calories and nutrients are absorbed. Malabsorptive weight loss surgeries, also called intestinal bypasses, are no longer recommended because they result in severe nutritional deficiencies. Combined operations use stomach restriction and a partial bypass of the small intestine. 

 Am I a Candidate for Weight Loss Surgery?
You may be a candidate for weight loss surgery if you have:

  1. a body mass index (BMI) of 40 or more about 100 pounds overweight for men and 80 pounds for women (see BMI chart)
  2. a BMI between 35 and 39.9 and a serious obesity-related health problem such as type 2 diabetes, heart disease, or severe sleep apnea (when breathing stops for short periods during sleep)
  3. an understanding of the operation and the lifestyle changes you will need to make.

 Is Weight Loss Surgery for You?
Bariatric weight loss surgery may be the next step for people who remain severely obese after trying nonsurgical approaches, or for people who have an obesity-related disease. Surgery to produce quick weight loss is a serious undertaking. Anyone thinking about undergoing this type of weight loss surgery should understand what it involves. Answers to the following questions may help you decide whether weight loss surgery is right for you.

Are you:

    * unlikely to lose weight or keep weight off long-term with nonsurgical measures?

    * well informed about the surgical procedure and the effects of the weight loss surgery?

    * determined to lose weight and improve your health?

    * aware of how your life may change after the operation (adjustment to the side effects of the operation, including the need to chew food well and inability to eat large meals)?

    * aware of the potential for serious complications, dietary restrictions, and occasional failures related to weight loss surgery?

    * committed to lifelong medical follow-up and vitamin/mineral supplementation?

Remember: There are no guarantees for any method, including surgery, to produce rapid weight loss and maintain it. Success with weight loss surgery is possible only with maximum cooperation and commitment to behavioral change and medical follow-up and this cooperation and commitment must be carried out for the rest of your life.

A decision to have bariatric surgery is very personal and very important. It will change your life in an irreversible way for the most part, not just because of the quick weight loss it produces. Being careful with a decision like this is the right thing to do. You should research the various weight loss surgeries and the various surgeons. Then you and the surgeon should, together, agree that weight loss surgery is the best choice you can make.

Considerations prior to weight loss surgery:

    * Can you comply with the therapy and follow up that is so necessary after weight loss surgery?

      You have to follow the directions of your surgeon, especially diet, exercise, labs and office follow up. The surgery is a tool only. Rapid weight loss and maintenance depends on your use of this tool. It would be disastrous if one depends on the surgery alone to take care of the obesity. There will never be a break in following the guidelines set forth by your surgeon regarding diet, exercise and follow up. You are making a life-long commitment.

   * Are you considering weight loss surgery for the right reasons? Do you just want to look better?

      Bariatric surgery is NOT done for cosmetic reasons. It is always done to improve failing health. If you meet the medical criteria, you are considering weight loss surgery for health reasons. Feeling better is the goal, looking better is a nice side effect.

    * Have you made many attempts at weight loss?

      Only you can decide if you have reached the point where you have exhausted all other options to lose weight. You are making a serious decision that only YOU can make, once you feel you are well informed about the risks and benefits of weight loss surgery.

    * Are you comfortable with your decision? Are you apprehensive?

      Once you are feeling comfortable with your decision to make a lifestyle change forever and you know you can do it, you are ready. If you know exactly and feel comfortable with how the weight loss surgery rearranges your digestive system and the short and long-term risks of bariatric surgery, you are ready. If you have found a surgeon that you feel very comfortable with, you are ready. If you are apprehensive about the whole process, you are normal!

 Types of Weight Loss Surgeries
There are several types of restrictive and combined operations that lead to rapid weight loss. Each one has its own benefits and risks. 

Restrictive Weight Loss Surgeries

Purely restrictive operations only limit food intake and do not interfere with the normal digestive process. To perform the operation, doctors create a small pouch at the top of the stomach where food enters from the esophagus. At first, the pouch holds about 1 ounce of food and later may stretch to 2-3 ounces. The lower outlet of the pouch is usually about ¾ inch in diameter or smaller. This small outlet delays the emptying of food from the pouch into the larger part of the stomach and causes a feeling of fullness, thus resulting in rapid weight loss in most patients.

After the operation, patients can no longer eat large amounts of food at one time. Most patients can eat about ¾ to 1 cup of food without discomfort or nausea, but the food has to be soft, moist, and well chewed. Patients who undergo restrictive procedures generally are not able to eat as much as those who have combined operations.

 1. Adjustable Gastric Banding (also known as the LAP-BAND) In this procedure, a hollow band made of silicone rubber is placed around the stomach near its upper end, creating a small pouch and a narrow passage into the rest of the stomach. The band is then inflated with a salt solution through a tube that connects the band to an access port placed under the skin. It can be tightened or loosened over time to change the size of the passage by increasing or decreasing the amount of salt solution.
weight loss surgery
Advantages of this weight loss surgery:

  • Simple and relatively safe
  • Short recovery period
  • Major complication rate is low
  • No removal of any part of the stomach or intestines
  • No altering of the natural anatomy
  • Very short recovery periods

Disadvantages of this weight loss surgery:

  • About 5% failure rate because of
    • Balloon leakage
    • Band erosion/migration
    • Deep infection
  • Identifying patients who will not eat through the operation is difficult

For additional support and information about this surgery visit the Lap-Band? Forum

 2.Vertical Sleeve Gastrectomy (also called vertical Sleeve Gastrectomy, Greater Curvature Gastrectomy, Parietal Gastrectomy, Gastric Reduction and even Vertical Gastroplasty) is performed by approximately 15 surgeons worldwide. The originally procedure, conceived by Dr. D Johnston in England, was called The Magenstrasse and Mill Operation. It generates rapid weight loss by restricting the amount of food that can be eaten (removal of stomach or vertical gastrectomy) without any bypass of the intestines or malabsorption. The stomach pouch is usually made smaller than the pouch used in the Duodenal Switch.

vertical sleeve gastrectomy

Advantages of this weight loss surgery:

  • Stomach volume is reduced, but it tends to function normally so most food items can be consumed in small amounts.
  • Eliminates the portion of the stomach that produces the hormones that stimulates hunger (Ghrelin).
  • No dumping syndrome because the pylorus is preserved.
  • Minimizes the chance of an ulcer occurring.
  • By avoiding the intestinal bypass, the chance of intestinal obstruction (blockage), anemia, osteoporosis, protein deficiency and vitamin deficiency are almost eliminated.
  • Very effective as a first stage procedure for high BMI patients (BMI >55 kg/m2).
  • Limited results appear promising as a single stage procedure for low BMI patients (BMI 35-45 kg/m2).
  • Appealing option for people with existing anemia, Crohn's disease and numerous other conditions that make them too high risk for intestinal bypass procedures.
  • Can be done laparoscopically in patients weighing more than 500 pounds

Disadvantages of this weight loss surgery:

  • Potential for inadequate weight loss or weight regain. While true for all procedures, it is theoretically more possible with procedures without intestinal bypass.
  • Higher BMI patients will may need to have a second stage procedure later to help lose all of their excess weight. Two stages may ultimately be safer and more effective than one operation for high BMI patients. This is an active point of discussion for bariatric surgeons.
  • Soft calories from ice cream, milk shakes, etc., can be absorbed and may slow weight loss.
  • This procedure does involve stomach stapling and therefore leaks and other complications related to stapling may occur.
  • Because the stomach is removed, it is not reversible. It can be converted to almost any other weight loss procedure.
  • Considered investigational by some surgeons and insurance companies.

For additional support and information about this surgery visit the  Vertical Sleeve Gastrectomy Forum

 3. Vertical Banded Gastroplasty (VBG) (see figure 3) VBG uses both a band and staples to create a small stomach pouch, resulting in quick weight loss. Once the most common restrictive operation, VBG is not often used today.

Advantages of this weight loss surgery:

  • completely reversible
  • body anatomy is left intact
  • no dumping syndrome
  • no nutritional deficiencies

Disadvantages of this weight loss surgery:

  • needs strict patient compliance to diet
  • no malabsorption
  • vomiting if food is not properly chewed or if food is eaten too quickly

For additional support and information about this surgery visit the Vertical Banding Forum

Advantages/Disadvantages Overview

Advantages: Restrictive weight loss surgeries are easier to perform and are generally safer than malabsorptive operations. AGB is usually done via laparoscopy, which uses smaller incisions, creates less tissue damage, and involves shorter operating time and hospital stays than open procedures. Restrictive weight loss surgeries can be reversed if necessary, and result in few nutritional deficiencies.

Disadvantages: Patients who undergo restrictive weight loss surgeries generally lose less weight than patients who have malabsorptive operations, and are less likely to maintain weight loss over the long term. Patients generally lose about half of their excess body weight in the first year after restrictive procedures. However, in the first 3 to 5 years after VBG patients may regain some of the weight they lost. By 10 years, as few as 20 percent of patients have kept the weight off. (Although there is less information about long-term results with AGB, there is some evidence that weight loss results are better than with VBG.) Some patients regain weight by eating high-calorie soft foods that easily pass through the opening to the stomach. Others are unable to change their eating habits and do not lose much weight to begin with. Successful results depend on the patient's willingness to adopt a long-term plan of healthy eating and regular physical activity.

Risks: One of the most common risks of restrictive operations is vomiting, which occurs when the patient eats too much or the narrow passage into the larger part of the stomach is blocked. Another is slippage or wearing away of the band. A common risk of AGB is breaks in the tubing between the band and the access port. This can cause the salt solution to leak, requiring another operation to repair. Some patients experience infections and bleeding, but this is much less common than other risks. Between 15 and 20 percent of VBG patients may have to undergo a second operation for a problem related to the procedure. Although restrictive operations are the safest of the bariatric procedures, they still carry risk in less than 1 percent of all cases, complications can result in death.

Because combined weight loss surgeries result in greater weight loss than restrictive operations, they may also be more effective in improving the health problems associated with severe obesity, such as hypertension (high blood pressure), sleep apnea, type 2 diabetes, and osteoarthritis.

Combined Restrictive/Malabsorptive Weight Loss Surgeries

Combined operations are the most common bariatric procedures. They restrict both food intake and the amount of calories and nutrients the body absorbs.

1. Roux-en-Y Gastric Bypass (RGB)This operation is the most common and successful combined weight loss surgery in the United States. First, the surgeon creates a small stomach pouch to restrict food intake. Next, a Y-shaped section of the small intestine is attached to the pouch to allow food to bypass the lower stomach, the duodenum (the first segment of the small intestine), and the first portion of the jejunum (the second segment of the small intestine). This reduces the amount of calories and nutrients the body absorbs. Rarely, a cholecystectomy (gall bladder removal) is performed to avoid the gallstones that may result from rapid weight loss. More commonly, patients take medication after the operation to dissolve gallstones. 

gastric bypass

Advantages of this weight loss surgery:

  • greatly controls food intake, leading to rapid weight loss
  • dumping syndrome dumping conditions to control intake of sweets
  • reversible in an emergency though this procedure should be thought of as a permanent

Disadvantages of this weight loss surgery:

  • staple line failure
  • ulcers
  • narrowing/blockage of the stoma
  • vomiting if food is not properly chewed or if food is eaten to quickly
  • weight re-gain is known to happen if dietary changes are not followed long term


Note (figure 4): This is the RNY without the stomach being transected or divided. This type RNY is not widely done anymore. Most surgeon perform the RNY with the stomach divided with no staple line. Transected means: stomach is completely separated from the new stomach

For additional support and information about this surgery visit the Roux-en-Y Forum

2. Duodenal Switch (also called vertical gastrectomy with duodenal switch, biliopancreatic diversion with duodenal switch, DS or BPD-DS) is performed by approximately 50 surgeons worldwide. It generates weight loss by restricting the amount of food that can be eaten (partial gastrectomy (i.e., partial removal of the stomach along the outer curvature see diagram) and by limiting the amount of food (specifically fat) that is absorbed into the body (intestinal bypass or duodenal switch). This weight loss surgery is more controversial because it has a significant component of malabsorption (bypass of the intestinal tract), which seems to augment and help maintain long-term weight loss. Of the procedures currently performed for the treatment of obesity, it has some powerful and effective components. Due to concerns of possible long-term effects of malabsorption and the technical difficulty involved with this type of weight loss surgery, many surgeons don't perform it.

duodenal switch

Advantages of this weight loss surgery:

  • More normal stomach allows for better eating quality, drink with meals
  • No dumping syndrome because the pylorus is preserved
  • Minimizes ulcer risk
  • Very effective for high BMI patients (BMI>55 kg/m2), but can be done on lower BMI just as effectively
  • The intestinal bypass is partially reversible for those having malabsorptive complications
  • Laparoscopic approach is offered by some surgeons

Disadvantages of this weight loss surgery:

  • Chance of chronic diarrhea, possibly more foul smelling stools and gas. This can be due to dieting intake, but for the most part controlled.
  • Malabsorption can lead to anemia, protein deficiency and metabolic bone disease in up to 5 percent of patients
  • Carbohydrates can be well absorbed and if eaten in significant quantities lead to inadequate weight loss
  • This procedure is the most complex surgical weight loss procedure. As with any of the surgeries listed complications can occur in high risk patients.(heart failure, sleep apnea)

For additional support and information on this surgery visit the Duodenal Switch Forum

To locate a Duodenal Switch surgeon in your area click here


3. Biliopancreatic Diversion (BPD) (see figure 5) In this more complicated combined weight loss surgery, the lower portion of the stomach is removed. The small pouch that remains is connected directly to the final segment of the small intestine, completely bypassing the duodenum and the jejunum. Although this procedure leads to weight loss, it is used less often than other types of operations because of the high risk for nutritional deficiencies. This surgery is not commonly done anymore.

Advantages of this weight loss surgery:

  • significant malabsorptive component
  • better chance of sustained weight loss
  • ability to eat larger quantities of food and still loose weight

Disadvantages of this weight loss surgery:

  • greater chance of chronic diarrhea, stomal ulcers, more foul smelling stools and flatus
  • higher risk of nutritional deficiencies
  • higher chance of micro-nutrient deficiencies such as vitamins and calcium

Advantages/Disadvantages Overview

Advantages: Most patients lose weight quickly and continue to lose for 18 to 24 months after the procedure. With the Roux-en-Y gastric bypass, many patients maintain a weight loss of 60 to 70 percent of their excess weight for 10 years or more. With BPD/DS, most studies report an average weight loss of 75 to 80 percent of excess weight. Because combined operations result in greater weight loss than restrictive operations, they may also be more effective in improving the health problems associated with severe obesity, such as hypertension (high blood pressure), sleep apnea, type 2 diabetes, and osteoarthritis.

Disadvantages: Combined procedures are more difficult to perform than the restrictive procedures. Such weight loss surgeries are also more likely to result in long-term nutritional deficiencies. This is because these weight loss surgeries causes food to bypass the duodenum and jejunum, where most iron and calcium are absorbed.

Menstruating women may develop anemia because not enough vitamin B12 and iron are absorbed. Decreased absorption of calcium may also bring on osteoporosis and related bone diseases. Patients must take nutritional supplements that usually prevent these deficiencies. Patients who have the biliopancreatic diversion procedure must also take fat-soluble (dissolved by fat) vitamins A, D, E, and K supplements.

RGB and BPD operations may also cause “dumping syndrome,” an unpleasant reaction that can occur after a meal high in simple carbohydrates, which contain sugars that are rapidly absorbed by the body. Stomach contents move too quickly through the small intestine, causing symptoms such as nausea, bloating, abdominal pain, weakness, sweating, faintness, and sometimes diarrhea after eating. Because the duodenal switch operation keeps the pyloric valve intact, it reduces the likelihood of dumping syndrome.

Risks with these weight loss surgery procedurs:In addition to risks associated with restrictive procedures such as infection, combined operations are more likely to lead to complications. Combined operations carry a greater risk than restrictive operations for abdominal hernias (up to 28 percent), which require a follow-up operation to correct. The risk of hernia, however, is lower (about 3 percent) when laparoscopic techniques are used.

As with any surgery, there can be complications. This list can include:

  • Deep vein thrombophlebitis

  • Non-fatal pulmonary embolus

  • Pneumonia

  • Acute respiratory distress syndrome

  • Splenectomy

  • Gastric leak and fistula

  • Duodenal leak

  • Distal Roux-en-Y leak

  • Postoperative bleeding

  • Duodenal stomal obstruction

  • Small bowel obstruction

  • Death

Laparoscopic Bariatric Surgery
In laparoscopy, the surgeon makes one or more small incisions through which slender surgical instruments are passed. This technique eliminates the need for a large incision and creates less tissue damage. Patients who are super-obese (more than 350 pounds) or have had previous abdominal operations may not be good candidates for laparoscopy, however. Adjustable gastric banding is routinely performed via laparoscopy. 

This technique is often used for Roux-en-Y gastric bypass, and although less common, biliopancreatic diversion can also be performed laparoscopically. The small incisions result in less blood loss, shorter hospitalization, a faster recovery, and fewer complications than open operations. However, combined laparoscopic procedures are more difficult to perform than open procedures and can create serious problems if done incorrectly.

Weight Loss Surgery for Adolescents
With rates of overweight among youth on the rise, weight loss surgery is sometimes considered as a treatment option for adolescents who are severely overweight. However, there are many concerns about the long-term effects of weight loss surgery on adolescents’ developing bodies and minds. Experts in pediatric overweight and bariatric surgery recommend that surgical treatment only be considered when adolescents have tried for at least 6 months to lose weight and have not been successful. Candidates for weight loss surgery should be severely overweight (BMI of 40 or more), have reached their adult height (usually 13 or older for girls, 15 or older for boys), and have serious weight-related health problems such as type 2 diabetes or heart disease. In addition, potential patients and their parents should be evaluated to see how emotionally prepared they are for the operation and the lifestyle changes they will need to make. Patients should also be referred to a team of experts in adolescent medicine and bariatric surgery who are qualified to meet their unique needs.

Benefits of Surgical Weight Loss
  • High Blood Pressure can often be alleviated or eliminated by weight loss surgery
  • High Blood Cholesterol in 80% of patients can be alleviated or eliminated and in as little as 2-3 months post-operatively.
  • Heart Disease in obese individuals is certainly more likely to be experienced when compared to persons who are of average weight and adhere to a strict diet and exercise regimen. There is no hard and fast statistical data to definitively prove that weight loss surgery reduces the risk of cardiovascular disease, however, common sense would dictate that if we can significantly reduce many of the co-morbidities that we experienced as someone that is obese, we can likewise that our health may be much improved if not totally restored.
  • Diabetes Mellitus can usually helped and based upon numerous studies of diabetes and the control of its complications, it is likely that the problems associated with diabetes will be arrested in their progression, when blood sugar is maintained at normal values.
  • Abnormal Glucose Tolerance, or Borderline Diabetes is even more likely reversed by gastric bypass. Since this condition becomes diabetes in many cases, the operation can frequently prevent diabetes, as well.
  • Asthma sufferers may find that they have fewer and less severe attacks, or sometimes none at all. When asthma is associated with gastroesophageal reflux disease, it is particularly benefited by gastric bypass.
  • Sleep Apnea Syndrome sufferers can receive dramatic effects and many within a year or so of surgery find their symptoms were completely gone, and they had even stopped snoring completely!
  • Gastroesophageal Reflux Disease can be greatly relieved of all symptoms within as little as a few days of surgery.
  • Gallbladder Disease can be surgically handled at the time of the weight loss surgery if your doctor has cause to believe that gallstones are present.
  • Stress Urinary Incontinence responds dramatically to weight loss, usually by becoming completely controlled. A person who is still troubled by incontinence can choose to have specific corrective surgery later, with much greater chance of a successful outcome, with a reduced body weight.
  • Low Back Pain and Degenerative Disk Disease, and Degenerative Joint Disease can be considerably relieved with weight loss, and greater comfort may experienced even after as few as 25 lost pounds.

Weight loss surgery is a highly personal decision; it is also a medical decision. Your doctor should discuss the risks and help you measure the probability of benefits so that you can make an informed decision

Always get the advice from your attending surgeon on the best surgical option for you. Information provided here is to give an understanding on the different surgery types available. Obesity Help strives to be the top weight loss site on the Web by providing you with helpful and complete information about weight loss surgery, but the advice of your attending surgeon should always supercede anything you learn here.