How Does Weight Loss Surgery Work?

Weight loss procedures, also known as bariatric or metabolic surgery, are medical treatments designed to help people who are struggling to lose weight through diet and exercise alone. These procedures work by restricting the amount of food the stomach can hold, reducing calorie absorption, or a combination of both. 

Weight loss surgery can lead to significant and sustained weight loss and reduce the risk of obesity-related conditions such as type 2 diabetes, heart disease and sleep apnoea.

Common weight loss procedures include:

• Gastric bypass surgery: Creates a small pouch at the top of the stomach and connects it directly to the small intestine, bypassing a large part of the stomach and some of the intestine to reduce calorie absorption.
• Gastric sleeve surgery: Also called sleeve gastrectomy, this removes a large portion of the stomach, creating a smaller, sleeve-shaped stomach that limits the amount of food you can eat.
• Gastric band surgery: Involves placing an adjustable band around the upper part of the stomach to create a small pouch, which restricts food intake.
• Gastric balloon: A non-surgical option where a balloon is temporarily inserted into the stomach to reduce its capacity and create a feeling of fullness.
• Endoscopic sleeve gastroplasty (ESG): A minimally invasive procedure that uses an endoscope (a long, thin tube with a camera) and a stitching device to reduce the size of the stomach without the need for surgery.

Benefits of Weight Loss Procedures

• Significant, lasting weight loss: Weight loss procedures can help achieve substantial and long-term weight loss, making it easier to maintain a healthy weight and lifestyle. Each type of procedure has a slightly different outcome, but in general around 90% of patients after bariatric surgery lose 50% of their excess body weight and keep it off long-term.
• Improved health outcomes: Bariatric surgery has been shown to improve many obesity-related health conditions, and reduce the risk of developing them. This is particularly true of type 2 diabetes, but also high blood pressure (hypertension), high cholesterol, sleep apnoea, and heart disease. It can also improve gastro-oesophageal reflux disease (GERD) and joint pain caused by osteoarthritis.
• Customisable options: With a variety of surgical and non-surgical procedures available, weight loss treatments can be tailored to meet your specific health needs, weight loss goals, and personal preferences.

Drawbacks of Weight Loss Surgery

• Cost: This will depend on the procedure and where you have it. A gastric balloon tends to cost from £2,000 to £5,000, with the surgery options usually costing considerably more. In some cases, weight loss surgery may be available on the NHS, if you are severely obese and fit the criteria. 
• Pain and nausea: These can be quite common after gastric surgery or balloon placement, but usually only last a few days.
• Drawbacks of sudden weight loss: These can include excess folds of skin where you have lost weight, or gallstones, which are small stones that form in the gallbladder.
• Making changes to how you eat: You’ll need to make changes to what you eat and drink, especially in the early weeks and months. You’ll need to eat slowly and only small amounts at a time. You might have to stick to fluids or soft foods for the first few weeks. 
• Not achieving the weight loss you expect: You might not lose as much weight as you hoped. Even with weight loss surgery, you’ll only achieve lasting weight loss if you make permanent changes to what you eat.

Risks of Weight Loss Surgery

Weight loss surgery is a common and safe procedure, but there are risks to any surgery. These can include:

• Infection: After any surgery there is a small risk that the wound could get infected. After gastric bypass or gastric sleeve surgery there is also risk that food could leak out, which can cause a serious infection in your abdomen.
• Blood clots: Clots such as deep vein thrombosis (DVT) or clots in your lungs (pulmonary embolism) are a small risk of any surgery.  
• Gastric band slipping: Occasionally after gastric band surgery, the band can move out of place. If this happens, you’ll need surgery to put it back or remove it.
• Blocked stomach or intestine: The gut can get narrower or blocked after weight loss surgery, which means food can get stuck. If you have a gastric balloon, there’s a risk it could deflate and move through your digestive system, causing a blockage.
• Malnutrition: Weight loss surgery can make it harder for your body to absorb nutrients from food, so there’s a risk of becoming malnourished. You’ll usually be advised to take vitamin supplements.

Weight Loss Surgery Explained

Here’s how the process typically works:

1.  Choose where to have it: In the UK, the clinic or hospital where you have the procedure should be registered with the Care Quality Commission (CQC) and the surgeon or other specialist who does the procedure should be registered with the General Medical Council (GMC), on the specialist register and have a licence to practise. 
2. Initial consultation: Book an appointment with your chosen qualified bariatric surgeon or specialist to discuss your weight loss goals, medical history, and the types of procedures that might be suitable for you. The specialist will assess your physical and mental health, as well as your eating patterns and how you’ve already tried to lose weight. This will help them decide if you’re suitable for weight loss surgery and recommend the best approach based on your needs.
3. Choose the right procedure: Based on your consultation, decide which weight loss procedure is most appropriate for your situation. Your specialist will help you understand the benefits, risks, and expected outcomes of each option.
4. Pre-surgery preparation: Follow the pre-surgery instructions provided by your specialist, which may include dietary changes, an exercise programme, and specific tests to ensure you are fully prepared for the procedure.
5. Have the procedure: On the day of the procedure, you will undergo surgery or treatment in hospital, usually under general anaesthetic. The duration and recovery time will depend on the type of procedure chosen.
6. Post-operative care and follow-up: After the procedure, you will receive guidance on post-operative care, including dietary adjustments, exercise, and lifestyle changes to help maintain your weight loss. Regular follow-up appointments with your specialist will help monitor your progress, check your health, give you the advice and support you need, including psychological support.
7. Lifelong changes: To get the full benefit of weight loss procedures you’ll need to make lifelong changes to the way you eat, as well as taking supplements. After weight loss surgery you should have follow-up appointments for the rest of your life.

Written by

William Amps Content Specialist

William is a content specialist based in London with over 5 years of experience in the healthcare and financial services sectors. He’s passionate about creating content that helps people feel informed and confident in their decisions. At Clear Living, William focuses on understanding the customer’s perspective, ensuring they find the support they need when making important choices.

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