During this gastric sleeve surgery, about 75–85% of the stomach is removed using a stapling device, reshaping it into a slender tube or ‘sleeve’. This limits portion sizes and supports reduced appetite.
Typically lasting one to two hours, the operation is done laparoscopically via small keyhole incisions during a general anaesthetic—helping speed up recovery and minimise pain.
Before any gastric sleeve surgery, it’s important to fully explore dieting, exercise, or medical treatment. If you are not sure about bariatric surgery, you may consider different obesity surgery options—such as gastric bypass operation or stomach band fitted. Each has its own benefits and risks of gastric sleeve surgery (and alternatives), which your surgeon will explain thoroughly.
Gastric sleeve surgery involves the removal of a large section of your stomach. Reducing the size of your stomach will restrict the amount you can eat. It will also reduce your appetite by decreasing the production of appetite stimulating hormones in your stomach.
The sleeve gastrectomy is usually performed as a laparoscopic procedure, through four or five keyhole incisions. The operation will take one to two hours and requires a general anaesthetic. A large part of your stomach will be removed. The remaining section will be shaped into a sleeve or tube about the size of a banana and sealed using staples.
You’ll usually stay in hospital for two to three nights and need two to three weeks off to fully recover. This whole process, including understanding the risks of gastric sleeve surgery, is clearly outlined from day one.
Gastric sleeve surgery does not alter the route that food takes through your digestive system and the remaining part of the stomach retains its ability to start the digestive process, so you will still be able to digest and absorb food normally.
– Effective appetite control: Removing appetite hormone-producing parts reduces hunger.
– Portion control: A smaller stomach means you feel full faster.
– Natural digestion: Food follows the usual digestive route, keeping absorption normal.
– Lower dumping risk: Compared to gastric bypass, the chances of dumping are reduced.
– Intact stomach function: Key nerves are preserved, supporting healthy digestion.
– Simpler follow-up: No band adjustments mean fewer clinic visits.
– High success rate: Most patients lose 50–60% of excess weight.
– Clear awareness: We openly discuss the risks of gastric sleeve surgery to ensure informed decisions.
The surgery is generally safe. But there might be some risks of gastric sleeve surgery, just like any other surgery. We discuss these thoroughly so you can make an informed decision.
Certain side effects can happen after gastric sleeve surgery. Side effects will usually only be temporary and they are generally mild.
– Mild soreness and swelling around incisions.
– Early eating discomfort.
These should go away once you heal, as long as you don’t overeat.
More serious complications can also happen when you have gastric sleeve surgery. This is when problems occur during or after the operation. Such problems are much less common than the milder side effects. Most people will not experience any serious complications from this surgery.
One potential risk of having the procedure is that you will need to be put under a general anaesthetic. Some people can have a bad reaction to the anaesthetic. Other potential complications associated with surgery include heavy bleeding and blood clots. The chance of surgical complications is low, but they are increased by conditions such as high blood pressure.
There is a chance your surgeon may need to convert your keyhole procedure to open surgery. This means making a bigger cut on your abdomen. This is only done if it’s impossible to complete the operation safely using the keyhole technique.
The chance of complications during or after the procedure will vary between individuals. Your surgeon will be able to provide personalised advice on the risks of weight loss surgery. In general, about 5% of people will experience some complications when having a sleeve gastrectomy. The chance of experiencing fatal complications during surgery is 0.2%.
A healthy diet and lifestyle will be essential for weight loss after surgery. Starting to make these changes before the operation can make recovery easier. Eating a calorie-controlled diet is especially important in the last few weeks as it can reduce the size of your liver and lower the risk of surgical complications. If you smoke, you should try to give up before the procedure as it could affect your healing and increase the risks of gastric sleeve surgery.
As it gets closer to the day of your operation, you should:
Patients choosing the cheapest gastric sleeve UK options are still advised to prepare properly—cost savings should never mean cutting corners on safety or aftercare.
You will need plenty of rest when you get home, but you should gradually be able to return to your normal routine over the next 2–3 weeks. However, you should avoid any heavy lifting or very strenuous activities for a couple of months.
The surgical wounds should heal in about a week. The dressings can then come off. You should look out for any signs of complications, such as swelling, pus or inflammation. About 5% of patients will experience some kind of problem after gastric sleeve surgery, but serious issues are rare.
You will have follow-up appointments to check on your recovery, but you should contact your doctor if you notice anything unusual or are experiencing severe discomfort. These steps are vital in reducing the risks of gastric sleeve surgery.
When you wake up in the recovery room after gastric sleeve surgery, you will probably feel a bit sore and drowsy. Your memory may be hazy for a while. You will have dressings over the surgical wounds in your abdomen and there may be tubes draining away excess fluid. You might also have a catheter.
The nurses will offer you something to drink and monitor your condition as you recover. You should soon be able to get out of bed and move around a little. You will usually need to spend 2–3 days in hospital after gastric sleeve surgery. You should arrange for someone to pick you up from the hospital as you won’t be able to drive until your surgical wounds have healed.
Your doctor will ensure that you have a personalised diet after gastric sleeve surgery. You will be on a liquid-only diet for the first few weeks. You can then begin to introduce some soft, moist foods that will be easy to digest. It will be about 4–6 weeks before you can start eating solids. Certain foods, such as white bread, rice, high-fibre vegetables and chewy meat may need to be reintroduced more slowly as they are more difficult to digest.
The sleeve gastrectomy should help you stick to your diet by restricting the amount you can eat and reducing your appetite. However, like all procedures, there may be some mild effects such as acid reflux, nausea or vomiting as your body adjusts. These are among the more manageable risks of gastric sleeve surgery, and they typically ease over time.
You should soon begin to lose weight and notice an improvement in your health, as long as you follow your diet.
All medical procedures come with a small risk of complications. Approximately 5% of people who have gastric sleeve surgery will have complications of some kind. Although these are usually relatively mild and easy to treat, they can sometimes be more serious. The complications are fatal in 0.2% of people.
Potential risks of sleeve gastrectomy include:
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