Mini Gastric Bypass

What is Mini Gastric Bypass Surgery?

The mini gastric bypass procedure is the newest bariatric procedure available. In its ten-year life span, it has proven to produce excellent long-term weight loss results. It can be seen as a halfway house between the sleeve gastrectomy and the Roux-en-Y bypass operation.

It’s a simple, short and inexpensive technique, carried out by keyhole surgery under general anaesthetic. The operation usually takes less than 60 minutes and the hospital stay is usually less than one day.

How Does Mini Gastric Bypass Surgery Work?

Dr Robert Rutledge, from the USA, first developed the mini gastric bypass procedure in 1997 to modify the standard Billroth II procedure.

The procedure:

  1. Access to abdominal cavity: Five small incisions are made on the abdominal wall to allow the insertion of access ports. Instruments are then passed through the various ports to complete the operation.
  2. Creation of the mini-stomach: The stomach is divided into two parts. One part is a long narrow tube that will serve as your new “mini-stomach”. The second part, the larger remaining part of your stomach, is “de-functionalised”; that is to say, it no longer receives or processes food.
  3. Bypass of the small intestine: The length of the small intestine bypassed varies from patient to patient, usually ranging from three to seven feet. The actual length of the intestine bypassed will be determined by your surgeon on multiple factors, including your height and weight, your weight-loss expectations, and a careful review of the risks and benefits of a shorter vs. a longer bypass.
  4. Connection of intestine to pouch: The small intestine is connected to the pouch creating the “bypass”. This can be done in many different ways, but most commonly is with a combination of staples and sutures.
  5. Removal of ports and closure of skin incisions: Upon completion of the operation, all instruments and ports are removed, and the five small skin incisions are closed with skin closure staples.

After surgery, the small pouch will help patients to eat smaller portions of food and feel fuller after eating. That food is diverted to the lower parts of the intestine, leading to the release of good hormones that impact the feeling of fullness. These hormones also help to switch off obesity-related medical conditions such as diabetes.



*As with any surgical procedure, there are possible risks and complications, including infection, leakage, excess skin, bowel obstruction, iron & calcium deficiencies, blood clot, pneumonia and death. These are uncommon and we will do everything possible to prevent them from happening.

Please speak to your Tonic surgeon to discuss the risks in more detail and any concerns you may have.

Weight Loss Results

Most patients typically lose 30–35% of their total body weight in the first nine to twelve months after surgery. The mini bypass will help patients to maintain a steady weight going into the future.


To prepare for the mini gastric bypass, patients will have a consultation with one of our surgeons in the clinic. The Tonic support team, including our specialist dietitian, psychotherapist and biometric specialist nurse, will be in touch to offer advice and prepare you for your mini gastric bypass.

Part of the preparation may also involve a liver-shrinking diet (800 calories a day) for around two weeks before surgery.

Recovery Time and Aftercare

Patients will be nursed on specialist bariatric wards. They can expect to be up and walking within three hours of the operation, drinking the same day and going home the next day. Most patients can expect to be back at work after seven to ten days. After the procedure, patients will be asked to go on a particular diet to help the healing.

Typically, this is a liquid-only diet for two weeks, a puréed diet for two weeks and then a soft diet for two weeks. From then on, patients will need to continue to eat in the right way, adopting an active and healthy lifestyle.

The first clinic appointment will be around six weeks after surgery. At this appointment, you will see your consultant, review how you have got on and address any issues or queries.

As patients will be eating small meals, they will be required to take vitamins and minerals to avoid deficiencies. These include calcium (with vitamin D), iron, multivitamins and three-monthly vitamin B12 injections. Blood tests are recommended every six to twelve months to ensure adequate supplementation.

Read more about our premium 5 year aftercare package at the bottom of this page.

Is Mini Gastric Bypass Surgery Right for You?

With excellent long-term weight loss, minimal pain and the option for reversal or revision should the need ever occur, it’s not surprising that people from across the world are choosing the mini gastric bypass over other types of weight loss surgery.


Gastric bypass procedures are available in London, Derby, Manchester, Leeds, Luton, Birmingham, Nottingham and Leicester, with finance options available.