Choosing a Type of Weight Loss Surgery
What is it? This is another form of restrictive weight loss surgery. In the operation, which is usually done with a laparoscope, about 75% of the stomach is removed. 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 sequence of weight loss surgeries. It can be followed up by gastric bypass or biliopancreatic diversion, if more weight loss is needed. However, in other cases, it might be the only surgery you need.
The Pros. For people who are very obese or sick, standard gastric bypass or biliopancreatic diversion may be too risky. A sleeve gastrectomy is a simpler operation that allows them a lower-risk way to lose weight. If needed, once they've lost weight and their health has improved -- usually after 12 months to 18 months -- they can go on to have a second surgery, such as gastric bypass. In people with high BMIs, sleeve gastrectomies result in an average weight loss of greater than 50% of excess weight.
Because the intestines aren't affected, a sleeve gastrectomy doesn't affect the absorption of food, so nutritional deficiencies are not a problem.
The Cons. Unlike gastric banding procedures, a sleeve gastrectomy is irreversible. Most importantly, since it's relatively new, the long-term benefits and risks are still being evaluated.
The Risks. Typical surgical risks include infection, leaking of the sleeve, and blood clots.
Gastric Bypass Surgery (Roux-en-Y Gastric Bypass)
What is it? Gastric bypass is the most common type of weight loss surgery. It combines both restrictive and malabsorptive approaches. It can be done as either a minimally invasive or open surgery.
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 a section of the stomach and the small intestine. Skipping these parts of the digestive tract means that fewer calories get absorbed into the body.
The Pros. Weight loss tends to be swift and dramatic. About 50% of it happens in the first six months. It may continue for up to two years after the operation. Because of the rapid weight loss, health conditions affected by obesity – such as diabetes, high blood pressure, high cholesterol, arthritis, sleep apnea, heartburn, and other conditions -- often improve quickly. You'll probably also feel a dramatic improvement in your quality of life.
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.
The Cons. By design, surgeries like this impair the body's ability to absorb food. While that can cause rapid weight loss, it also puts you at risk of serious nutritional deficiencies. 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 is "dumped" 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 sugary or high-carbohydrate foods, and adjusting the diet helps. However, some experts actually see dumping syndrome as beneficial, in that it encourages people to avoid foods that could lead to weight gain.
Unlike adjustable gastric banding, gastric bypass is generally considered irreversible. It has been reversed in rare cases. Therefore, getting this surgery means that you're permanently changing how your body digests food.
The Risks. Because these weight loss surgeries are more complicated, the risks are higher. The risk of death from these procedures is low -- about 1% -- but they are more dangerous than gastric banding. Infection and blood clots are risks, as they are with most surgeries. Gastric bypass also increases the risk of hernias, which can develop later and may need further surgery to fix. Also, a side effect of rapid weight loss can be the formation of gallstones.