It's more than just

Gastric Bypass Surgery

It’s the opportunity to finally take control of your weight for good with gastric bypass surgery

Gastric bypass

By Mr Rishi Singhal MBBS, MRCS, FRCS, MD

Last review: 21/04/2022. All content on this page is reviewed by a multi-disciplinary team lead by Mr Rishi Singhal.

What is a gastric bypass?

The gastric bypass is a long established weight loss procedure. Over 30 years it has proven to be safe and effective, delivering both excellent weight loss outcomes and significant health benefits. In fact, for people experiencing health problems associated with their weight, the bypass is generally the best procedure available.

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We have been doing the gastric bypass for over 15 years and our team has experience of over 5,000 procedures.

Patients can expect to lose about 70% of their excess weight within 2 years of surgery and those with health problems such as type 2 diabetes, sleep apnoea or reflux disease can expect an immediate improvement in their condition. Often, medication can be stopped immediately.

Above is a short video about the gastric bypass and how it works. In addition to covering the traditional Roux en Y gastric bypass, we also provide information about the Mini (or ‘loop’) bypass which is an alternative that is growing in popularity. As with all your surgery options there are pros and cons for each and we’ll explain those to you here and, hopefully, when we meet you in clinic for consultation.

Am I eligible for the gastric bypass?

There are many factors to consider for eligibility but we generally offer the gastric bypass procedure to those with a minimum body mass index (BMI) of 35.

The gastric bypass operation

The simplest way to describe it is to say that the stomach and bowel are ‘re-plumbed’ so that the food you eat goes into a reduced stomach before passing directly into the bowel a little further down the bowel than was the case before.

The bypass works in two ways. Firstly, by reducing the size of the stomach and so restricting the amount of food that can be eaten. We usually reduce the stomach’s capacity by as much as 90-95%. On this page we give a technical breakdown of how the procedure is done.

How much weight will I lose with the gastric bypass?

Of course, the main benefit people are seeking when they have bypass surgery is to lose weight. There are other significant benefits however, especially where improvements in health are concerned. Those people who are managing health problems associated with their weight can expect significant improvements after bypass.

Typically, we expect gastric bypass patients to lose 60-70% of their excess weight over a 2-year period, and most of this weight is lost in the first year after surgery*. You will see from our case studies that some people lose all their excess weight. To compensate there will be some who lose a little less. For this reason, 60-70% is a reasonable expectation. Weight loss results will differ from person to person and your results, especially in the long term, will depend on how well you are able to adapt your lifestyle and eating habits. For this reason, although the gastric bypass procedure itself is extremely powerful, the support and guidance from our bariatric aftercare team is vital to helping you learn and embed the skills needed to maximise and to maintain your weight loss (see before and after photos and stories from gastric bypass patients here).

Weight loss example

  • A 5ft 6in person weighing 17st (240lbs / 109kgs) has an ideal weight of about 11st (154lbs / 70kgs)
  • They are carrying excess weight therefore of 86lbs (240lbs actual weight minus 154lbs ideal weight)
  • 70% of 86lbs is around 60lbs
  • So, this person could expect to lose (on average) about 60lbs (27kgs).

Scientific evidence suggests that most gastric bypass patients who comply with the follow-up requirements, including nutritional recommendations, do very well, and see great long-term results*. Moreover, compared with obese individuals who have not had surgery, gastric bypass patients have a much lower risk of premature death and disability.

*JAMA. 2012 Jan 4;307(1):56-65. doi: 10.1001/jama.2011.1914. Bariatric surgery and long-term cardiovascular events

Gastric bypass success stories

gastric bypass weight loss surgery success story before and after

From Nearly 20 Stone with a Binge Eating Disorder to Fitness Fanatic

Before and after of gastric bypass patient Georgina

The Gastric bypass Saved Georgina from Going Blind

What are some health benefits of weight loss surgery?

Turning to the health benefits bypass patients can expect, it’s a long list and the improvements are usually very significant. In many cases people see a complete resolution of their symptoms for the problem they are managing.  Here are some of the more common weight related health problems and the benefit people can expect.**

As specialists in weight loss surgery we are familiar with all the health issues associated with obesity. It is also our duty to inform all our patients of the risks and potential complications of gastric bypass surgery, you can view these here. If you have specific health question, please do contact our team and we’ll be pleased to discuss them with you.

Video: How my health improved after weight loss surgery

**Buchwald H et al. Bariatric surgery: a systematic review and meta-analysis. JAMA. 2004 Oct 13;292(14):1724-37.

Gastric bypass cost and finance

At Healthier Weight we provide you with a fixed price gastric bypass package. With this package you have certainty of the cost of your treatment, including aftercare, blood tests and any treatment required in relation to a complication arising from your procedure. You can read more about our gastric bypass aftercare and support package here.


Put simply, it means you can go ahead with surgery safe in the knowledge that you will be faced with unexpected additional costs in the future.


The fixed price of your gastric bypass will vary depending on several factors including your location, the type of gastric bypass (primary or revision) and any special treatment requirements that are identified in the pre-operative period.


In order to help as many people as possible gain access to our services, we have developed a number of monthly payment plans plans tailored to the needs of our patients.


The importance of aftercare and support is often underestimated with the gastric bypass. Often people think the procedure is so powerful that they lose weight without too much effort, especially in the early months. However, over time the power of bypass will subside, and it will be the diet, eating and exercise changes that you have made in the years after your surgery that will help you maintain your weight loss.

Our team is here to see you in clinic and to provide the support you need for enduring success.

With this in mind, we have developed an aftercare and support package that we consider to be the most comprehensive of its type in the UK.

Our aftercare package has been developed to provide everything you need for success.


Get well on your way with all the essential rolled into one package
  • Lifelong support
  • 1 surgeon review when medically indicated
  • Virtual clinic review with specialist bariatric nurse at 12 months
  • Blood tests at 6 months
  • Long term follow up calls:
    3 days, 10 days, 3 weeks, 2 months, 3 months, 6 months, 12 months, 18 months & 24 months
  • 12 months access to the Healthier Weight platform/app
  • 1 x 1-2-1 appointments with dietician*


Our most comprehensive aftercare package with live support for 2 years
  • Lifelong support
  • 1 surgeon review when medically indicated
  • Virtual clinic review with specialist bariatric nurse at 12 months
  • Blood tests at 6 months
  • Long term follow up calls:
    3 days, 10 days, 3 weeks, 2 months, 3 months, 6 months, 12 months, 18 months & 24 months
  • 24 months access to the Healthier Weight platform/app
  • 4 x 1-2-1 appointments with dietician*
  • Set of WiFi scales
  • 1-2-1 appointment with health coach*
Save £600


Extra nutritional advice from an expert bariatric dietitian
  • Lifelong support
  • 1 surgeon review when medically indicated
  • Virtual clinic review with specialist bariatric nurse at 12 months
  • Blood tests at 6 months
  • Long term follow up calls:
    3 days, 10 days, 3 weeks, 2 months, 3 months, 6 months, 12 months, 18 months & 24 months
  • 18 months access to the Healthier Weight platform/app
  • 2 x 1-2-1 appointments with dietician*
  • Set of WiFi scales

*Hosted on the Healthier Weight app

Gastric bypass common FAQs

This depends upon what you do for a living, but if you have a sedentary occupation you can generally expect to be back at work about 2 weeks after gastric bypass, after which time the wounds should have healed and you will be feeling more comfortable. If you have a physically demanding job involving lifting etc, you may need a little longer. The bowel and stomach inside your abdomen will be healed in around 6-8 weeks, so during this period it is important that you follow the nutritional guidelines as closely as you can.

Your long term success with your procedure is dependent on high quality aftercare. Anyone who has had weight loss surgery will tell you this is crucial. All too frequently, overseas surgery packages have no aftercare.

In the UK surgeon outcomes are monitored closely. There is a duty of candour and transparency. In many overseas countries the same standards do not apply.

We have seen many botched procedures from overseas that come with limited aftercare and warranties. You won’t receive any support from any serious problems that arise post-op, and you will ultimately go onto the NHS waiting list for your procedure to be put right.

Generally there is minimal scarring with a gastric bypass. The operating ports are placed in the abdomen through 5 narrow (0.5 cm) incisions which are sutured and/or glued and will normally heal in about 10-14 days. The scars should fade gradually. Some individuals have a greater tendency to form keloid which may result in thicker and more prominent scars.

You may eat most foods that don’t cause you discomfort. However, because you can only  eat small amounts, it is important to include foods rich in protein but low in fat and sugar. We encourage you to eat vegetables, fruit, wholegrains, lean meat and fish. You will be provided with detailed nutritional information following your gastric bypass surgery.

Mr Rishi Singhal MBBS, MRCS, FRCS, MD

Mr Rishi Singhal MBBS, MRCS, FRCS, MD

Mr Singhal is an expert bariatric surgeon based in the West Midlands and also Medical Director at Healthier Weight

For the first time in a very long time I have something to look forward to – seeing the new me adapt to my new life. I took control of my life. In the last year I’ve changed my job and I’ve found love. I would recommend this to anyone.

Call our specialist team today on
0800 313 4618 
Get a quote 
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