People who have bariatric surgery tend to lose much more weight than people who get medical treatment for their weight loss. This means that surgery is more likely to help with health conditions linked to obesity. These may include diabetes, heart disease, arthritis, or sleep apnea. But the results vary. Some people can have large weight loss with medical treatment alone. And some people don’t lose as much weight as they want after surgery.

Surgeons do bariatric surgery using a number of different methods. The type of bariatric surgery that works best for you will depend on several factors. These include your general health, your medical needs, and your own preference. The types of surgery include:

• Lap banding. This surgery is also known as laparoscopic adjustable gastric banding or LAGB. During lap banding your surgeon places an adjustable band around the top of your stomach. Your surgeon also places a small device called a port under the skin of your abdomen. A thin tube leads from the band to the port. Fluid is injected into the port and flows to the band to make it squeeze tighter around the top of the stomach. Or fluid can be removed through the port to loosen the band. The band around your stomach reduces the amount of food that you can eat at one time.

• Gastric bypass. This is also called a Roux-en-Y gastric bypass. This surgery also reduces the amount of food you can eat at one time. And it reduces the number of calories and nutrients you can absorb from the foods you eat. During gastric bypass, your surgeon separates part of the stomach to create a small pouch. The pouch is then attached to a part of your small intestine. This small pouch holds less food, making you feel full faster. As food bypasses the rest of the stomach and upper part of your small intestine, you absorb fewer calories and nutrients.

• Sleeve gastrectomy. This is a type of surgery that removes up to 85% of the stomach. It’s also known as a gastric sleeve. The surgery turns the stomach into a narrow tube that looks like a sleeve. The sleeve holds much less food, and you feel full faster. Your stomach also makes less of the main hormone that causes hunger.

• Biliopancreatic diversion with duodenal switch (BPD/DS). This is a less common type of weight-loss surgery. In this procedure, your surgeon removes part of the stomach to create a gastric sleeve, as with the sleeve gastrectomy. The sleeve is then attached to a part of the lower small intestine. The sleeve holds much less food, and your body absorbs far fewer calories and nutrients from food.

All surgery has risks. Your risks may vary according to your general health, your age, the type of surgery you choose, and the amount of weight you need to lose. Talk with your healthcare provider about the risks that most apply to you. Risks of bariatric surgery include:

• Bleeding

• Infection

• Blockage of your bowels (intestinal blockage)

• Blood clots in your legs that may travel to your lungs or heart 

• Heart attack

• Need for follow-up surgery

• Gallstones (a later complication)

• Nutritional problems (a later complication)

• Mental health problems after the procedure

• Weight regain

You will get instructions about how to adapt to your new diet after your surgery. You will likely be on liquid nutrition for a few weeks after surgery. Over time, you’ll start to eat soft foods and then solid foods. If you eat too much or too fast, you will likely have stomach pain or vomiting. You’ll learn how to know when your new stomach is full.

Your healthcare provider or nutritionist will give you more instructions about your diet. These may vary depending on the type of surgery you had. You’ll need to learn good habits like choosing healthy foods and not skipping meals. Your healthcare provider or nutritionist may also need to screen you for low levels of certain nutrients. This is more of a problem with gastrectomy, gastric bypass, and BPD/DS surgery.

You may need to work with your healthcare providers ongoing to stay healthy. This depends on what type of surgery you have. Your medical team will keep track of your health, especially as you lose weight quickly in the first 6 months or so after your surgery. Weight loss tends to be at its peak around a year after surgery.

Work with your healthcare provider to see which surgery may work for you. It’s important to have sensible goals about what bariatric surgery might achieve for you. Some people may still be somewhat overweight a year or two after their surgery. Even if you don’t lose all of your excess weight, health issues such as high blood pressure should get better. You may be able to reduce the amount of medicines that you need to take.

Talk with your healthcare provider. Ask questions and express your concerns. Together you can decide the right treatment for your needs.