Reclaim Your Life With Gastric Bypass Surgery


Gastric bypass surgery is a laparoscopic ‘keyhole’ procedure, performed while you sleep under a general anaesthetic.

A gastric bypass is recommended for patients with a BMI (Body Mass Index) between 40 – 55. On average, patients tend to lose 30% of their total body weight during treatment, and 70% of their excess fat weight.

The procedure changes how and what you can eat:

  • Reducing the portion size of the food you eat, and eating less food overall, patients generally feel more satisfied after eating, and have less desire to eat.
  • Due to the shortening of your small intestine, there is a reduction in the absorption of nutrients and calories from the food you eat. 
  • Some people are less able to  tolerate foods containing fat, sugar, starch and sometimes milk, as well as they used to. 
  • If you eat too much of these types of foods you may actually start to feel ill, but this ‘side effect’ in itself could help you make dietary and lifestyle changes to achieve long term weight loss.


This is an operation where some of the stomach and part of the small intestines are bypassed. 

The stomach is stapled to leave a smaller pouch, and then a section of the small intestine is attached to the small stomach pouch that has been created.


Professor Purkayastha explains the benefits of Gastric Bypass surgery, and for which people this might be the better choice of surgery.

Next steps

If you are interested in Gastric Bypass surgery, please book a complimentary call with our friendly Patient Concierge team. 

They will listen to your story, answer your questions, and ask about your health goals. If you are ready, they will get you booked in to meet your surgeon for a pre-surgery metabolic assessment and consultation.

Initial Metabolic Assessment With Your Surgeon
  • Review of your weight history
  • Assessment of your current health picture
  • Explore your motivation and goals
  • Understanding your readiness and support structure
  • Bespoke treatment pathway designed for you
  • Build trust with your surgeon and care team
60-minute consultation
This amount will be deducted from your bariatric package if you decide to go ahead with weight loss surgery.
Online & In-Person Consultations Available


Here are some questions about Gastric Bypass surgery we are frequently asked by patients. We believe it is important you have all the information you require, so you can make an informed decision if surgery is the right option for you.

People who choose Gastric Bypass Surgery can enjoy sustainable and long-term significant weight loss. This is because the surgery involves reducing the size of the stomach pouch and bypassing a section of the small intestine. Reduced stomach size results in you feeling full more quickly and reduces the intake of food.

The surgery also aids weight loss by causing hormonal changes that reduce your feelings of hunger caused by the ‘hunger hormone’, Ghrelin. 

Although each individual is different, on average someone who has Gastric Bypass surgery can lose up to 80% of excess body weight in the first 18 months after surgery. 

The positive health outcomes from Gastric Bypass surgery include significant weight loss and the reduction of conditions related to increased weight. This includes but not limited to:

  • Type 2 Diabetes (Gastric Bypass is often recommended to people who have a 5+ year history of type 2 diabetes and who need insulin injections)
  • High Cholesterol
  • High Blood Pressure 
  • Heart Disease 
  • Stroke
  • Mobility issue
  • Joint pains
  • Cancer
  • Sleep Apnoea
  • Infertility

Weight loss and better health can also improve the quality of your life and mental health, boosting self confidence and opening up new doors for how you want to live your life

Professor Puraksyastha will walk you through the preparation steps in the weeks leading up to your Gastric Bypass surgery. The support you are given is tailored to you, following full metabolic, dietetic and psychological assessments. This is to ensure the best preparation and outcomes possible.

Our specialist dietitian will help you to prepare for your Gastric Bypass surgery by undergoing a pre-operative liver-reduction diet lasting two weeks. The diet is low in fat and moderate in protein and low in calories, providing approximately 800-1000 kcal per day. The aim of the pre-operative diet is to shrink your liver meaning it can be moved more easily, making the operation safer. In the 24 hours before your surgery, you will be required to restrict your food and drink intake. 

Our specialist psychotherapists will also help you to be best prepared for your surgery, ensuring you have the psychological support to ensure best outcomes.

Dietary changes

There are three stages of texture modification diet following surgery, starting with a liquid diet and gradually building this back up to a long term, solid textured food.

Your specialist dietitian will help explain and guide your through the post-operative diet which follows the below stages:

  • liquid diet (10 days)
  • puree diet (3-4 weeks)
  • soft diet (for around 6 weeks)

This is followed by a lifelong healthy, high protein diet of a normal solid texture from 12 weeks onwards.

Fluid intake remains important and you should aim to drink 1.5 litres a day.  Avoid high calorie fluids including hot drinks made with sugar and fizzy drinks as these can cause bloating and discomfort.

Alcohol should not be taken for three months after surgery and after this time in moderation after food.  

Lifestyle changes

Exercise –  After surgery we advise you to move around as much as possible and ensure that you don’t get dehydrated.  Exercise should be gentle for the two months –  i.e. swimming, walking, cycling. No heavy lifting or weight training for at least eight weeks

In the long-term increased activity levels are needed alongside a reduced dietary intake for optimal and sustained weight loss after bariatric surgery.

Driving – You should not drive for the first two weeks following surgery and contact your insurance to find out what their guidelines are.  

We suggest that when you are ready to drive that you ask a family member or a friend to drive you to a quiet street where you can attempt an emergency stop. If it feels comfortable then it is fine for you to drive.

Travel – We advise that you do not take a long haul flights for 8 weeks following your surgery

You can take flights of no more than 2 hours duration from two weeks after your surgery

Pregnancy – We advise you to avoid pregnancy for 2 years after surgery. Oral contraception can be restarted 1 month after surgery

Smoking – It is strongly advised to quit smoking in the long-term as this can undo the positive health outcomes from surgery, and increases risk of ulceration in the gastric pouch, chest infections, cancers and heart disease.

After your recovery period has ended, you can start to enjoy the lifestyle changes that come about from better health and increased mobility associated with Gastric Bypass surgery.

Your aftercare package includes prolonged support from Mr. Purkayastha and your specialist dietitian, as well as the wider Surgical WeightMatters team. 

You will have in-person follow-up appointments with Mr. Purkayastha arranged 7-10 days, 3 months, 6 months and 12 months after surgery with the option of additional follow-up appointments to check in with your progress. 

You will have several post-operative appointments with your specialist dietitian as well, which are spread over 2 years after your surgery and tailored to suit your needs.

There is no limit to how many sessions you can have with the Surgical WeightMatters team. We are with you every step of the way to ensure the best support and outcomes possible.

My Purkayastrha will take time to talk you through the risks involved and ensure you are fully informed before consenting to Gastric Bypass surgery. 

Every effort ensures these risks are avoided, and Mr Purkayastha is an extremely experienced bariatric surgeon. However, there are short and long-term risks to the Gastric Bypass surgery which include:

Short-term risks:

  • Pain 
  • vomiting
  • Bleeding
  • Infection of the wound
  • Adverse reactions to anaesthesia
  • Blood clots
  • Breathing problems
  • Leaks from the cut edge of the stomach
  • Potential complications from nutritional deficiencies
  • Dumping syndrome 

Long-term risks:

  • Gastrointestinal obstruction
  • Hernias
  • Gastroesophageal reflux
  • Low blood sugar (hypoglycemia)
  • Malnutrition, food intolerances or Dumping Syndrome
  • Vomiting
  • Blood clotting
  • Stomach ulcers
  • Barrett’s oesophagus

Weight regain, if diet and lifestyle changes are adhered to lifelong habits

Complications during surgery can result in elective or emergency medical or surgical (reoperation) treatment.


This animation explains the changes made to your digestive system during gastric bypass surgery.


Speak with our friendly patient concierge team, and let us answer any questions you have about weight loss surgery.


Your weight loss surgery journey starts when you meet your Bariatric Surgeon for a pre-surgery metabolic assessment and consultation.

It is important you can ask all the questions you have about surgery, and make a connection with the person who will perform your surgery.

Weight & Health History

Current Health Status

Goals & Aspirations

Pros & Confs of Different Surgeries

Bespoke Surgical Pathway Created For You


Your surgeon will work closely with your Multidisciplinary Team (MDT), a Bariatric Dietitian and Bariatric Psychotherapist . Together they will ensure you are fully prepared for your surgery.

All pre-surgery blood work is included in your bariatric package. In some instances we may require additional diagnostic tests, or refer you to a consultant in our wider MDT; Endocrinologist, Sleep Specialist, Bariatric Psychiatrist.

Your safety and care is at the heart of what we do. Exceptional outcomes come from good preparation and planning, and an integrated team that shapes your treatment to your individual needs. 

Bariatric Dietitian Assessment & Pre-Surgery Diet Plan

Bariatric Psychotherapist Assessment & Motivation

Pre-Surgery Bloods & Other Diagnostics

Anaesthetist Care Call

Pre-Surgery Consultation With Your Surgeon


Your weight loss surgery includes a 2-night stay, in a private room, at the prestigious King Edward VII hospital, located in central London’s world-class medical district.

On arrival you will be met by your Specialist Nurse Practitioner, who will guide you through each step of your hospital stay.

Your surgeon will meet you before your surgery, and will check in with you, and your progress, the day after your surgery.

Specialist Nurse Practitioner Orientation

2-Night Private Room Stay

Weight Loss Surgery Procedure

Hospital Aftercare & Surgeon Assessment

Discharge Care Plan & Medication


Exceptional outcomes from weight loss surgery come from good planning and preparation, medical excellence at every touch point, and aftercare support that guides positive behaviour change.

Your bariatric team works with you closely over the next 2-years, as you adjust and transition to the opportunities and life changes post-surgery. 

Sessions with your Bariatric Surgeon, Dietitian and Psychotherapist will be complemented by monthly group sessions and motivational email support, all curated with ongoing guidance from your Patient Concierge team.

Surgeon Follow-Up Consultations

Diagnostics Bloods Included

Ongoing Dietitian & Psychotherapist Support

Monthly Support Groups & Email Motivation

Patient Concierge Care & Guidance


We believe it is important to be upfront and transparent about the costs of the various bariatric surgeries we provide.

The price below is for your Gastric Bypass 2-Year Package.

Click on the buttons to see exactly what is included in the price, and any additional extras that you may encounter.

Most Popular
Plan 6-month 1-year 2-year
Bariatric Package £19,300 £20,750 £22,600
(less initial consultation)
Surgeon Pre-Op Consultation
Anaethetist Care Call
Psychological Preparation
Dietitian Readiness
Hospital Stay
Surgeon Fees
Anaethetist Fees
Hospital Stay – Private Room 2 nights 2 nights 2 nights
Take-Home Medication included included included
Aftercare 6 months 1 year 2 year
Surgeon Follow-Ups
(includes diagnostic blood tests)
2 consultations 3 consultations 5 consultations
Psychological Coaching 4 hours 8 hours
Dietitian Support 4 hours 4 hours 8 hours
Patient Concierge

** This fee is the full amount that the majority of our patients pay for this bariatric procedure, however, some patients may require an additional level of support.
Transparency on cost is one of our core values, so we will always be clear and upfront if we think your care requires an extra layer of medical excellence, and the fees associated with this.


  • Diet and lifestyle assessment with a specialist bariatric dietitian
  • Eating and psychological assessment with a specialist bariatric psychotherapist
  • Pre-surgical blood tests
  • Final surgical readiness consultation with your bariatric surgeon
  • Dedicated patient concierge scheduling your appointments and answering any questions you have


  • Pre-operative assessment
  • Welcome call with your specialist nurse practitioner who will be your hospital care coordinator
  • 2-night hospital stay in a private room at the King Edward VII hospital
  • All hospital fees associated with your bariatric procedure, including post-op blood analysis
  • Anaesthetist fees on the day of your surgery
  • Surgeon fees for your surgery and next-day review
  • 48-hour post-surgery on-call availability of your surgeon (if required)
  • 2-weeks of take-home medication you require as you leave hospital and transition back home


  • Follow-up consultations with your bariatric surgeon at 10 days – 3 months – 6 months – 1-year
  • Diagnostic blood tests included at all of these appointments
  • 4-hours of dietetic support with your bariatric dietitian, to guide and coach you through transitions in your eating and lifestyle behaviour
  • 4-hours of psychological support to help you shape a positive mindset, and develop new healthy habits
  • Dedicated patient concierge to answer any questions you have, and help you schedule appointments
  • Monthly patient online group support meetings, facilitated by our dietitian and psychotherapy teams
  • Curated workflow of timed emails to educate, motivate and inspire you to achieve exceptional outcomes

Initial Consultation With Your Surgeon

The pre-surgery metabolic assessment and consultation is not included in your package price, as some people may decide that weight loss surgery is not the right treatment pathway for them. The cost of this 60-minute consultation is £400.

Additional Diagnostic Testing

Your bariatric surgeon may request you have additional diagnostic testing before or after your surgery. We list the types of diagnostics below, and will provide the current price of the test at the time of referral.

  • CT Abdomen / Pelvis
  • CT Chest
  • Water Soluble Contrast Swallow & Meal

Hospital Accommodation

Your 2-night hospital stay in a private room is quoted for standard ward accommodation. Extra fees apply when you choose to stay an extra night the day before your surgery, or in the extremely rare situation when a complication may require an extra level of hospital care. We list the types of additional accommodation below, and will provide the current price list at the time your surgery is booked.

  • Pre-Surgery Accommodation
  • Standard Ward Accommodation
  • HDU Accommodation
  • ICU Accommodation