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The Bariatric Service (Weight Loss Surgery) at St George’s Hospital has been established for over 40 years. We have gained considerable experience and moved with the times regarding new and improved approaches to managing obesity and weight related health problems.

St George’s Hospital Multidisciplinary Bariatric Team (MDT) provides a comprehensive service. All of our team have a specialist interest and dedication to the treatment of obesity as a medical condition. Our multidisciplinary team includes Bariatric surgeons, Endocrinologists, a Clinical Psychologist and Psychiatrist, a Clinical Nurse Specialist, specialist Anaesthetist and Specialist Bariatric Dietitians. Patients are supported and motivated on every step of the pathway in order to achieve the best possible results.

St George’s Bariatric service is a ‘tertiary referral centre’. This means we are experienced and equipped to handle the most complex of cases. We also accept referrals from anywhere in the UK for patients with post-operative difficulties.

If you feel that you may benefit from weight loss surgery then please discuss this with your GP. Your GP can then contact us as long as you meet the criteria for referral. Keep in mind that weight loss surgery is not a cosmetic procedure. Bariatric surgery is solely aimed as a metabolic treatment and is reserved for those struggling to manage weight related health problems including blood pressure, diabetes, cholesterol or cardiovascular disease.

Referral Criteria

St George’s Hospital accepts referrals based on a locally agreed policy which has been developed in collaboration with local stakeholders . In summary our weight loss service accepts referrals for the following category of patients 

  1. Patients with a BMI of over 40
  2. Patients with a BMI of between 35 kg/m^2 and 40 kg/m^2 and any of the following comorbidities:
    1. Type 2 diabetes.
    2. Sleep apnoea requiring CPAP
    3. Documented symptomatic atherosclerotic disease e.g. ischaemic heart disease.
    4. Poorly controlled hypertension.
    5. Poorly controlled hyperlipidaemia.

It should be noted that for patients with BMI of 35 to 40 kg/m^2, referrals for consideration for surgery on the grounds of poorly controlled hypertension and hyperlipidaemia would be typically only accepted if the referral was supported by secondary care physician (e.g. Hypertension Specialist or Metabolic Physician).

Please note that osteoarthritis, infertility and polycystic ovarian syndrome would not normally be considered comorbidities mandating referral for consideration for  bariatric surgery for patients with a BMI of under 40 kg/m^2.

Initial Assessment Pathway

Following referral patients will typically undergo an initial medical assessment. This assessment will comprise of a detailed review of medical issues; diet and exercise activity; and where appropriate a psychological assessment.

As a general rule following referral to our weight management service all patients would be expected to undergo a “Tier 3 style” programme which typically consists of engagement in a diet and exercise programme for a minimum period of one year.  In addition, during this year-long period patients would be expected to demonstrate sustained weight loss of 5-10% of total bodyweight.

For patients who have extreme obesity or pressing medical co-morbidities this period of Tier 3 engagement may, at the discretion of the MDT, be abridged.

Patients who fail to demonstrate at least 5% weight loss (and particularly those who gain weight following referral) would not normally be referred on for consideration for bariatric surgery.  In addition patients who were smokers on referral to our service would be expected to demonstrate smoking cessation for at least 12 months before referral for consideration for bariatric surgery.

Patients who do demonstrate engagement and appropriate weight loss over a 1 year period may then be referred on for consideration for bariatric surgery. Please note that achievement of these criteria does not mean you are automatically referred for surgery- the decision to offer surgery is based on an individual assessment of the risk/benefits of surgery.

Bariatric Surgical Pathway

On referral to the surgical pathway patients will be invited to St George’s Hospital for a assessment with one of our surgical experts. Much consideration is given to working with patients to decide on the most appropriate surgical option. Further assessments may then be undertaken by psychologists and dieticians depending on your individual circumstances.

On completion of assessments, your case will be discussed by the multi-disciplinary team (MDT) who will then decide on a plan that is tailored for your needs and medical circumstances. Some patients require further work up before surgery whilst other can be added onto the waiting list for surgery.

Keep in mind that weight loss surgery is a ‘tool’ to help enable you to sustain diet/lifestyle changes in the long term. This is what gets the best results. If you feel that your diet and activity habits could be better, then why not start making changes before you undergo surgery. Doing so will ensure the best possible outcomes for health and weight loss. There are some links below that may help inspire you to get started. They may also help in keeping you motivated to sustain recent changes and demonstrated weight loss.


Additional Information

To find out more about our Bariatric Services, please click the following links:

ou may wish to research weight loss surgery a little more. We encourage all our patients to read up on weight loss surgery, however reliable information can be hard to find. The following links are approved by St George’s Hospital:


Good reading on weight loss surgery:

Cut down to size, achieving success with weight loss surgery:

Jenny Radcliffe. ISBN-10: 0415683777 ISBN-13: 978-0415683777

Return to Slender:

Carol Bowen Ball – Bariatric Cookery. ISBN-10: 0956662609 ISBN-13: 978-0956662606

Patient support group meetings

Monthly support group meetings for all pre and post operative Bariatric Surgery patients:

If you would like a personal point of information and insight about the challenges that bariatric surgery brings then feel free to come to one of our monthly patient support group meetings. You will have the chance to listen to patients that have already undergone bariatric surgery and have any question answered. This is a friendly informal meeting and all members of the public are welcome. Please note the discussion points are not appropriate for children and may be distressing.

These sessions will take place on the last Tuesday of each month except in May and August. We meet in the Hyde Park Room on the first floor of the Lanesborough Wing (next door to main restaurant) at 6.00pm – 8.00pm

Click here for information on how to loose weight healthily

Metabolic Bariatric Surgery Assessment Questionnaire

All patients must complete and return prior to any Bariatric team discussions or decisions.

[PDF01-BQ and word document to be linked here]


Please return via post to Bariatric Department, Jasmin Annex, St George’s NHS Trust, Blackshaw Road, Tooting, London SW17 0QT or emailed to Hermine.Lewis@stgeorges.nhs.uk


Pre-op Liver Reduction Diet Options (LRD)

Timeline Overview of Eating Post-op Eating Progression

Post-op Eating Stages and Helpful Food Suggestions

Helpful Tools and Apps to Help Monitor Your Nutritional Intake

If planning to attend for a blood test – please read the information on the link below and book an appointment in advance by either calling 0203 376 8776 or using the online booking portal provided in the link below: Blood Testing Services – St George’s University Hospitals NHS Foundation Trust (stgeorges.nhs.uk)

 Additional information on surgical procedures at the IFSO.com website

Sleeve Gastrectomy
Laparoscopic Sleeve Gastrectomy | Roux-en-Y Gastric Bypass (ifso.com)

Gastric Bypass
Gastric Bypass Surgery | Morbid Obesity (ifso.com)

One Anastomosis Gastric Bypass
One Anastomosis Gastric Bypass | Roux-en-Y Bypass (ifso.com)

Single Anastomosis Duodenal-Ileal Bypass with Sleeve (SADI-S)
Laparoscopic Single Anastomosis Duodenal-Ileal bypass with Sleeve (SADI-S) | Morbid Obesity (ifso.com)

A podcast discussing Bariatric Surgery with psychologist Denise Ratcliffe

102 Living with Bariatric Surgery: A Conversation with Author Denise Ratcliffe, DClinPscyh (weightlosssurgerypodcast.com)

 Healthy Eating Resources

Mental Wellbeing Self-Help Resources

Psychological Tools for Unhelpful Eating Behaviours

Additional support if struggling with eating disorders


Physical Activity Resources

For additional support and information Home › WLS Info

Additional information if struggling with weight regain post-bariatric surgery bariatric-surgery-tips_v3.pdf (easo.org)