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WEIGHT LOSS CLINIC — BRISBANE
Weight Loss
Surgery Types
The most common bariatric procedures performed in Australia — what each involves, how they work, and what to expect as part of a supervised weight loss journey with MedSurg.
Bariatric Surgery in Australia
Bariatric surgery remains the most effective long-term treatment for obesity. When combined with ongoing medical, nutritional and lifestyle support, it can achieve significant and sustained weight loss — and reduce or resolve many of the health conditions associated with excess weight.
This page provides an overview of the procedures most commonly performed in Australia, along with what each involves and what to expect. Your MedSurg doctor will discuss which procedure may be most appropriate for your individual circumstances, and coordinate referral to a bariatric surgeon if surgery is the right pathway for you.
Eligibility: Weight loss surgery is generally considered for people with a BMI of 35 kg/m² or higher, or a BMI between 30–35 kg/m² with an obesity-related condition such as type 2 diabetes, cardiovascular disease, high blood pressure, or obstructive sleep apnoea. Individual assessment is always required — check your BMI here.
For an overview of how MedSurg supports patients before and after surgery — including dietitian, psychology and exercise physiology input — visit our Surgical Weight Loss service page. To learn about the surgeons we work with, visit Meet Our Surgeons.
Laparoscopic Sleeve Gastrectomy (LSG)
Also known as a Sleeve or Stomach Stapling · Restrictive procedure
The Laparoscopic Sleeve Gastrectomy is the most widely performed primary bariatric procedure in Australia. According to the Bariatric Surgery Registry’s 2022 Annual Report, it accounted for 80% of the 16,308 bariatric procedures registered that year.
The operation involves removing approximately two-thirds of the stomach, leaving behind a narrow, tube-shaped “sleeve.” Only the stomach is altered — the small intestine remains untouched, which distinguishes the LSG from bypass procedures.
Beyond physical restriction, most patients notice a meaningful reduction in hunger and an earlier sense of fullness. This is partly due to changes in appetite-regulating hormones that occur following the procedure.
- Average total body weight loss at 1 year: approximately 31%
- Complication rate within 90 days: 1.3% (BSR 2022)
- Small intestine is not altered
- The most commonly chosen primary bariatric procedure in Australia
No procedure is without risk. The risks and benefits of LSG should be discussed thoroughly with your surgeon before proceeding. Registry figures represent population-level data and may not reflect individual outcomes.
Roux-en-Y Gastric Bypass (RYGB)
Restrictive & malabsorptive · Primary or revision procedure
The Roux-en-Y Gastric Bypass promotes weight loss through two mechanisms — restriction and malabsorption. It is also one of the most effective surgical treatments for gastro-oesophageal reflux disease, and is used both as a primary procedure and as a revision option following previous bariatric surgery.
Restriction: The surgeon divides the stomach using a surgical stapler, creating a small new pouch roughly the size of an egg. This limits how much food can be eaten at one time.
Malabsorption: The small intestine is rerouted and attached to this pouch further along the digestive tract, bypassing a section of bowel and reducing the number of calories absorbed from food.
The bypassed loop of bowel — still connected to the original stomach — is then rejoined further down the intestine, allowing digestive juices to mix with food and maintain proper digestion. Surgeons have performed this procedure safely for decades.
- Average total body weight loss at 1 year: approximately 31%
- Complication rate within 90 days: 1.3% (BSR 2022)
- Small intestine is not altered
- The most commonly chosen primary bariatric procedure in Australia
One Anastomosis Gastric Bypass (OAGB)
Also known as Mini Gastric Bypass or Omega Loop Bypass · Restrictive & malabsorptive
The One Anastomosis Gastric Bypass is closely related to the Roux-en-Y Gastric Bypass, with two key differences: the gastric pouch created is typically longer, and only one surgical join (anastomosis) is required rather than two.
Like the RYGB, it is both a restrictive and malabsorptive procedure. Patients eat smaller volume meals, and food entering the digestive tract bypasses approximately 150 cm of small bowel, reducing overall calorie absorption and supporting sustained weight loss.
The OAGB is well-suited to patients managing obesity alongside gastro-oesophageal reflux disease, and is generally considered a technically simpler procedure to perform than the RYGB.
- Works through both restriction and malabsorption
- One surgical join only (compared to two in RYGB)
- Suitable where reflux disease is also present
- Lifelong daily multivitamin supplementation required
Important: Patients who have had any form of bypass surgery are at lifelong risk of nutrient deficiency and must take a daily multivitamin. Other risks include marginal ulcers and dumping syndrome. These can be significantly reduced with the ongoing support of a specialist bariatric doctor, surgeon and dietitian.
Laparoscopic Adjustable Gastric Band (LAGB)
Purely restrictive · Adjustable & reversible
The Laparoscopic Adjustable Gastric Band was widely performed before the development of the Sleeve Gastrectomy, and remains the only purely restrictive bariatric procedure — no bowel is removed or rerouted. The band is placed laparoscopically (keyhole) around the upper stomach to limit how much food can pass through at once, and can be adjusted or removed entirely.
While patient and surgeon preference has largely shifted toward the Sleeve Gastrectomy, some patients still choose the LAGB as their first intervention, and many people continue to manage their weight with an existing band in place.
- No stomach removal or bowel rerouting
- Adjustable restriction — tightened or loosened over time
- Reversible — can be removed if needed
- Short hospital stay, low overall mortality rate
Experiencing problems with an existing band? If you have concerns — including pain, reflux, vomiting, weight regain or other symptoms — please contact us to arrange a review. Individual circumstances always need to be assessed before specific advice can be provided, and some patients with troublesome symptoms may benefit from band removal.
Benefits of Bariatric Surgery
Bariatric surgery is the most effective weight loss treatment available. Beyond the weight loss itself, surgery can significantly improve or resolve many of the health conditions associated with obesity.
- Reversal of type 2 diabete
- Remission of obstructive sleep apnoea
- Reduction in high blood pressure (hypertension)
- Improvement in lipid and cholesterol profiles
- Improvement in male and female fertility
- Improved quality of life
- Reduction in the risk of obesity-related cancers
- Decreased cardiovascular risk for heart attack and stroke
- Improvement in heart failure and fatty liver disease
- Reduced risk of developing osteoarthritis, particularly of the knee
If you would like to know more about whether weight loss surgery may be right for you, please book an appointment with your MedSurg Weight Loss doctor today.
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