Surgery

Restrictive Surgeries

They work by shrinking the size of the stomach and slowing down digestion. A normal stomach can hold about 3 pints of food. After surgery, the stomach may at first hold as little as an ounce, although later that could stretch to 2 or 3 ounces. The smaller the stomach, the less you can eat. The less you eat, the more weight you lose.

Malabsorptive/Restrictive Surgeries

They change how you take in food. They give you a smaller stomach and also remove or bypass part of your digestive tract, which makes it harder for your body to absorb calories. Doctors don’t do purely malabsorptive surgeries — also called intestinal bypasses — anymore because of the side effects.

Implanting an Electrical Device

This the newest of the three techniques, prompts weight loss by interrupting nerve signals between the stomach and the brain.

Adjustable Gastric Banding

What it is:
Gastric banding is a type of restrictive weight loss surgery.

How it works:
The surgeon uses an inflatable band to squeeze the stomach into two sections: a smaller upper pouch and a larger lower section. The two sections are still connected by a very small channel, which slows down the emptying of the upper pouch. Most people can only eat a 1/2 to 1 cup of food before feeling too full or sick. The food also needs to be soft or well-chewed.

Pros:
This operation is simpler to do and safer than gastric bypass and other operations. You get a smaller scar, recovery is usually faster, and you can have surgery to remove the band.
You can also get the band adjusted in a doctor’s office. To tighten the band and further restrict your stomach size, the doctor injects more saline solution into the band. To loosen it, the doctor uses a needle to remove liquid from the band.

Cons:
People who get gastric banding often have less dramatic weight loss than those who get other surgeries. They may also be more likely to regain some of the weight over the years.

Risks:
The most common side effect of gastric banding is vomiting after eating too much too quickly. Complications with the band can happen. It might slip out of place, become too loose, or leak. Some people need more surgeries. As with any operation, infection is a risk. Although unlikely, some complications can be life-threatening.

Sleeve Gastrectomy

What it is:
This is another form of restrictive weight loss surgery. In the operation, the surgeon removes about 75% of the stomach. What remains of the stomach is a narrow tube or sleeve, which connects to the intestines.
Sometimes, a sleeve gastrectomy is a first step in a series of weight loss surgeries. For some people, it’s the only surgery they need.

Pros:
For people who are very obese or sick, other weight loss surgeries may be too risky. A sleeve gastrectomy is a simpler operation that gives them a lower-risk way to lose weight. If needed, once they’ve lost weight and their health has improved — usually after 12 to 18 months — they can have a second surgery, such as gastric bypass.
Because the intestines aren’t affected, a sleeve gastrectomy doesn’t affect how your body absorbs food, so you’re not likely to fall short on nutrients.

Cons:
Unlike gastric banding, a sleeve gastrectomy is irreversible. Since it’s relatively new, the long-term benefits and risks are still being evaluated.

Risks:
Typical risks include infection, leaking of the sleeve, and blood clots.

Gastric Bypass Surgery (Roux-en-Y Gastric Bypass)

What it is:
Gastric bypass is the most common type of weight loss surgery. It combines both restrictive and malabsorptive approaches.
In the operation, the surgeon divides the stomach into two parts, sealing off the upper section from the lower. The surgeon then connects the upper stomach directly to the lower section of the small intestine.
Essentially, the surgeon is creating a shortcut for the food, bypassing part of the stomach and the small intestine. Skipping these parts of the digestive tract means that the body absorbs fewer calories.

Pros:
Weight loss tends to be swift and dramatic. About 50% of it happens in the first 6 months. It may continue for up to 2 years after the operation. Because of the rapid weight loss, conditions affected by obesity — such as diabetes, high blood pressure, high cholesterol, arthritis, sleep apnea, and heartburn — often get better quickly.
Gastric bypass also has good long-term results. Studies have found that many people keep most of the weight off for 10 years or longer.

Cons:
You won’t absorb food the way you used to, and that puts you at risk for not getting enough nutrients. The loss of calcium and iron could lead to osteoporosis and anemia. You’ll have to be very careful with your diet, and take supplements, for the rest of your life.
Another risk of gastric bypass is dumping syndrome, in which food dumps from the stomach into the intestines too quickly, before it’s been properly digested. About 85% of people who get a gastric bypass have some dumping. Symptoms include nausea, bloating, pain, sweating, weakness, and diarrhea. Dumping is often triggered by eating sugary or high-carbohydrate foods, and adjusting your diet helps.
Unlike adjustable gastric banding, gastric bypass is generally considered irreversible. It has been reversed in rare cases.

Risks:
Because gastric bypass is more complicated, it’s riskier. Infection and blood clots are risks, as they are with most surgeries. Gastric bypass also makes hernias more likely, which may need further surgery to fix. Also, you may get gallstones because of the rapid weight loss.

Maestro Rechargeable System

What it is:
The Maestro Rechargeable System  works like a pacemaker to deliver electrical pulses to a nerve between the stomach and brain, called vagus nerve. This nerve tells the brain when the stomach is full. The device is implanted in the abdomen and has a remote control that can adjust it from outside the body. The system is programmed to deliver a pulse — 5 minutes on and 5 minutes off — to the vagus nerve during your waking hours, and it’s supposed to turn off during the hours you sleep.

Pros:
Implanting this device is the least invasive of the weight loss surgeries. The outpatient procedure may take up to an hour and a half while the patient is under general anesthesia.

Cons:
The device has to be charged once or twice a week. If the battery completely drains, a doctor has to reprogram it. Side effects can include nausea, vomiting, heartburn, problems swallowing, belching, mild nausea, and chest pain.

Risks:
Infection, pain at the implantation site, or other surgical complications.

Biliopancreatic Diversion

What it is:
This is a more drastic version of a gastric bypass. The surgeon removes as much as 70% of your stomach and bypasses even more of the small intestine.
A somewhat less extreme version is biliopancreatic diversion with a duodenal switch, or “the duodenal switch.” It’s still more involved than a gastric bypass, but this procedure removes less of the stomach and bypasses less of the small intestinethan biliopancreatic diversion without the switch. It also makes dumping syndrome, malnutrition, and ulcers less common than with a standard biliopancreatic diversion.

Pros:
Biliopancreatic diversion can result in even greater and faster weight loss than a gastric bypass. Although much of the stomach is removed, what’s left is still larger than the pouches formed during gastric bypass or banding procedures. So you may be able to eat larger meals with this surgery than with others.

Cons:
Biliopancreatic diversion is less common than gastric bypass. One of the reasons is that the risk of not getting enough nutrients is much more serious. It also poses many of the same risks as gastric bypass, including dumping syndrome. But the duodenal switch may lower some of these risks.

Risks:
This is one of the most complicated and riskiest weight loss surgeries. As with gastric bypass, this surgery poses a fairly high risk of hernias, which will need more surgery to correct. But this risk is lower when the doctor uses minimally invasive procedures (called laparoscopy).