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Gastric bypass

Gastric bypass

NEW: The UK's most comprehensive gastric bypass package

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What is a gastric bypass?

Gastric bypass diagram
The gastric bypass or “Roux-en-Y” gastric bypass surgery combines restriction and an effect on gut hormones to deliver long-term weight loss. The 1.5 hour laparoscopic (keyhole) operation involves dividing the stomach and the bowel. In expert hands it is a safe, very effective form of weight loss surgery

How a gastric bypass works?

For years it was thought that gastric bypass resulted in significant calorie malabsorption, ie. calories from food and drink could not be absorbed across the wall of the bypassed section of the small bowel. This is not the case. Contrary to popular belief (and what you may have been told by other clinics) a gastric bypass is not a malabsorptive procedure.

Exactly how gastric bypass surgery produces such impressive long term weight loss is not yet fully understood but studies have shown that although an element of calorie malabsorption is present early after surgery, this is relatively short-lived. Instead, it seems that gastric bypass has a major impact on various gut hormones, some of which are involved in appetite regulation.

The gastric bypass procedure works to produce weight loss in two ways. Firstly by restriction as the new small pouch created by the surgeon represents only about 5% of the total stomach volume. This means you can only eat a very small amount of food before feeling full.

Secondly by an impact on gut hormones. Levels of the appetite stimulant ghrelin fall after gastric bypass surgery, which may explain why patients experience such a marked loss of appetite. Bypass patients also see profound changes in taste and food preferences away from fatty, sugary foods and this change in eating habits may further contribute to weight loss*.

For more info, see Gastric Bypass FAQs

Sharon is a gastric bypass patient from Manchester (November 2018). She said:

'My experience with Healthier Weight has been excellent throughout. From the  Patient care Co-ordinator, Cavell, to the nursing team through to the hospital team at the wonderful Priory hospital. Mr Singhal was the ideal surgeon throughout. My procedure was complicated because I’d had invasive abdominal surgery over 30 years ago. Mine was a complicated case! Mr Singhal planned my treatment and made sure everything went well. I had mini gastric bypass surgery and  I couldn’t recommend the service highly enough’ 

Is a gastric bypass right for you?

In 2014 NICE updated its advice on weight loss surgery on the NHS, particularly for patients with Type II diabetes. Although gastric bypass is the most common procedure undertaken on the NHS it's a fact that only 1% of those in the UK who would benefit actually have one.

We'll assess your eligibility for a private gastric bypass at consultation but as a general guide, you may be eligible if your BMI is 35kg/m2 or over and after trying other ways to lose weight without success, you know you need a permanent intervention. You can see the eligibility criteria we apply for bypass patients hereIf you don't feel that you could comply with the lifestyle changes of a gastric band or you suffer with related conditions, e.g. Type 2 diabetes, hypertension, then a gastric bypass offers the best possible results with regards to getting your weight under control and dramatically reducing the associated health risks. For more information on how these two operations compare, please see our gastric bypass v gastric band page.

There is also a variation of the bypass procedure known as the mini gastric bypass. For more information on this, along with how it compares with the standard gastric bypass operation, please see here.

Check your BMI here


*Weight loss surgery results and benefits differ for each individual. Results cannot be guaranteed
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The UK's most comprehensive gastric bypass package

Aftercare nurse

Careful long-term follow-up is essential to you achieving your weight-loss goals and avoid nutritional and metabolic complications. At Healthier Weight we offer a standard bypass package and a NEW upgrade package

The upgraded package includes:    

  • Complication cover - 24 months complications cover
  • Blood tests by HW - Blood tests conducted by HW at 6, 12 and 18 months
  • Surgeon Reviews - 1 surgeon review when clinically indicated
  • Extended nurse review - 30-40 minute consultation with a nurse at 12 and 24 months
  • Long term follow up calls - Calls at 3 days, 3 weeks, 7 weeks, 3m, 6m, 9m, 12m, 18m and 24m. Any clinic reviews where necessary
  • Access to Healthier Weight - Lifelong access to our team via phone
  • Post op food included - Soups, shakes and meals to guide you through the pre and post op nutrition requirements.

Compare our bypass packages

Finance plans
Spread the cost of your procedure over 4 years
with our Flexible Finance Options

Gastric bypass before and after stories

Gastric bypass success story - Andrea after surgery
"I had struggled with my weight all my life. I tried every diet as well as medication from the GP and pills from the internet" 

Andrea's 10 stone weight loss weight improved her mobility and reduced her worsening join pain*.

Gastric bypass testimonial by Lloyd - Post-surgery photo

"Now I am so much more confident. I came off my blood pressure tablets more or less straight after the operation" 

Lloyd is literally half the man he was after losing 17 stone with a gastric bypass procedure*.

Gastric bypass story - Jenny after

"I hated the way I looked and the struggle I had to find clothes... from one month to the next, I'd move up another dress size" 

Jenny took the decision to have a gastric bypass procedure and has since lost 8 stone*.

Gastric bypass story - Duncan after
"I began to realise that things in my life needed to change so I could be around for my daughter in years to come" 

Duncan lost 11 stone with a bypass and eradicated his sleep apnoea and snoring issues*.

Woman on scales small
Weight loss results and procedure outcomes comparable
with the best centres of excellence around the world

Weight loss with a gastric bypass

Typically, we expect gastric bypass patients to lose 60-70% of their excess weight over a 2-year period, although the majority of this weight is lost in the first year*. Weight loss results for each bypass patient are however different and your results will depend on how well you adapt your lifestyle and eating habits. A gastric bypass is extremely effective if you follow our guidelines, but it is important to remember that it is not a “cure” for your weight problems, rather a powerful tool to help you manage your weight.

An example of expected weight loss:

  • A 5ft 6in person weighing 17st (240lbs / 109kgs) has an ideal weight of about 11st (154lbs / 70kgs)
  • They are carrying excess weight therefore of 240lbs minus 154lbs = 86lbs.
  • 70% of 86lbs is around 60lbs
  • So this person could expect to lose (on average) up to 60lbs (27kgs) which is between 4 and 4½ stones in weight*

Scientific evidence suggests that the majority of 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.

Excess or loose skin following a bypass

Due to the considerable amount of weight that gastric bypass patients typically lose*, it's possible that you will experience some excess, loose or saggy skin. This most commonly occurs in the abdominal apron, or trunk area. The amount of excess skin you'll be left with following a gastric bypass operation varies and will depend upon your age and weight before the procedure. Generally, the heavier and older you are, the more likely you are to have extra skin. Younger patients tend not to have as much loose skin due to greater natural skin elasticity.
30 day surgical warranty
Peace of Mind Cover Included at no charge
within all 2 Year Gastric Bypass Packages

Benefits and risks of gastric bypass

Health benefits

In addition to weight loss*, the health benefits of gastric bypass surgery can be substantial and sometimes dramatic, resulting in major reductions in various co-morbidities – including type II diabetes which is more often than not completely cured after this procedure. Some of these are listed below:

  • Type II diabetes: 80% of patients will have complete resolution of their diabetes
  • Hypertension: 85-90% of patients reduce or stop their anti-hypertensive (blood pressure) medication
  • Dyslipidaemia: 90-95% of patients show major improvement or complete resolution of abnormal cholesterol
  • Sleep apnoea: 80-85% of patients discontinue CPAP†. Improved sleeping patterns, snoring and daytime fatigue 
  • Reflux: 95% of patients will experience major and rapid resolution of symptoms  
  • Stress incontinence: The majority of patients experience marked improvement or complete resolution of symptoms    
  • Infertility and PCOS*: 95% of patients experience correction of underlying hormonal problems and restored fertility    
  • Asthma: Patients with asthma see marked improvement in symptoms and a reduction in medication     
  • Liver disease (NASH)¶: 85-90% of patients will have complete resolution of the disease   
  • Back pain and arthritis: Patients experience marked reduction in joint and back pain and increased mobility   
  • Psychological wellbeing: Reduced depressive symptoms and anxiety, improved social interaction and overall quality of life    

† Continuous Positive Airways Pressure     * Polycystic ovarian syndrome     ¶ Non-Alcoholic Steatohepatitis

Risks and side effects

Although there is no doubt that a gastric bypass operation can be both life-transforming and life-saving, the decision to go ahead with surgery is a serious one. You should choose your bypass surgeon with care as this is not a procedure for the general surgeon and should only be carried out by those specially trained in obesity surgery. That's why we only work with the world's finest bariatric surgeons. In experienced hands, however the operative risks and likelihood of developing long-term complications are relatively small. The early complication rate is approximately 6% (6:100) and the overall mortality rate is low at around 0.3% (3:1000). Operative risks include:

  • Haemorrhage (bleeding)
  • Anastomatic leakage (ie leakage around where the bowel is joined to stomach or bowel)
  • Adverse reactions to anesthesia and/or medication
  • Blood clots (Deep vein thrombosis in the legs / Pulmonary embolus on the lungs)
  • Infection
  • Death

It is possible to develop long-term complications in the years that follow and the most common post-operative problems relate to nutritional deficiency. As gastric bypass surgery can significantly reduce the absorption of key vitamins and minerals, particularly vitamin D, B12, folate, iron and calcium, it can be associated with long-term nutritional deficiencies which may result in anaemia and bone diseases such as osteoporosis. To avoid these nutritional deficiencies and any associated complications, you will be required to take intensive vitamin and mineral supplementation for life. It is also important to have regular blood checks to monitor your vitamin and mineral stores.

Dumping Syndrome is also a problem that can occur in gastric bypass patients and is caused by the consumption of sugar. Symptoms include abdominal cramping and diarrhoea. Some people will also regain some weight in subsequent years; more on dumping syndrome.

Healthier Weight is the first private clinic in the UK to offer a non-surgical gastric bypass revisional procedure in order to help overcome some of the longer term problems and complications that can occur following a gastric bypass. More information is available on that here.

For prices & finance options, get a quote online or call 0121 693 4488

*Weight loss surgery results and benefits differ for each individual. Results cannot be guaranteed

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*Weight loss surgery results and benefits vary and are different for each individual. As such, Healthier Weight cannot guarantee specific weight loss goals.