Display Patient Information Leafelts

Roux-en Y gastric bypass

Date issued: October 2021

Review date: October 2023

Ref: B-319

Pdf: Roux-en Y gastric bypass final October 2020 v9.pdf [pdf] 405KB


Introduction ………………………………………….. page 3
Surgical overview …………………………………….page 3
Preparation for surgery …………………………….. page 8
Pre-operative liver reducing diet ………………….. page 10
Hospital admission ………………………..…………page 15
Post-operative period in hospital .………………..…page 17
Advice on discharge ………………………………….page 18
Recommended vitamin and mineral supplements…page 20
Follow-up appointments …………………………..… page 22
Blood tests ……………………………………………..page 23
Potential complications of surgery …………………..page 24
Nutritional information after surgery ……………..…page 30
Healthy lifestyle choices ……………………….…….page 38
Support Group and Contact details …………………page 39


This information booklet has been developed to help prepare you for bariatric surgery. It covers what you can expect before, during and after your stay in hospital and helps you with the lifestyle changes you need to make after surgery.

Remember, this is the beginning of a challenging journey and it is important that you are well prepared with information and determination to maximize your chances of improving your health and achieving your goals.

Surgical overview

Bariatric or Metabolic surgery has grown in popularity because it produces sustainable long-term weight loss in most patients and many problems associated with obesity such as diabetes and sleep apnoea are improved or completely resolved. It is important to note that any improvement in type II diabetes may not be lifelong. Diabetes is a chronic disease and can relapse. Despite this, surgery is currently the most effective treatment for type II diabetes. Both sleeve gastrectomy and gastric bypass can be used to treat type II diabetes.

There are several types of bariatric surgery however the two procedures offered within the Plymouth Hospitals Trust are the laparoscopic Roux-en-Y gastric bypass and the laparoscopic Sleeve Gastrectomy.

The Roux-en-Y gastric bypass

This procedure involves creating a very small pouch out of the stomach and attaching it directly to the small intestine, bypassing most of the stomach and the first part of the small bowel. This small stomach pouch cannot hold large amounts of food and by skipping the first part of the small bowel, hormones that control our appetite and food absorption are also affected. Together, this results in significant and sustained weight loss.

The sleeve gastrectomy

This procedure involves reducing the size of the stomach by 75-80% of its original size. Weight is lost because of early satiety (the feeling of fullness after eating), largely due to the smaller size of stomach. Also, some appetite-stimulating hormones normally produced by the stomach are reduced by the procedure. Apart from this, the stomach digests calories and nutrients in an almost normal way.

Some patients, especially those with a BMI >50-55kg/m2 are at higher risk for complications of bariatric surgery because of either medical conditions related to obesity, or technical difficulty in performing the procedure due to the patient’s size. The sleeve gastrectomy can usually be achieved in these cases relatively quickly and safely as a laparoscopic (keyhole) operation and the patient can lose significant amounts of weight.

What is Laparoscopic Surgery?

Laparoscopic surgery involves several very small incisions rather than one large incision that is used in open surgery. Harmless gas is introduced into the abdomen, inflating it, and creating a space for the surgeon to work. The surgeon introduces a long narrow camera and surgical instruments, and uses these to perform the procedure.

Laparoscopic procedures have many advantages, including less pain, a shorter hospital stay, and a quicker recovery, as well as significantly reduced risk of wound infection or hernias. If for some reason your surgeon cannot complete the procedure laparoscopically, they can convert to the open procedure safely. The chance of this occurring is low, and would only be done in your best interests.

Improved health

Bariatric surgery reduces the risk of death from obesity. Many obesity-related conditions such as type II diabetes, obstructive sleep apnoea, joint pain, lipid (cholesterol) abnormalities, high blood pressure and fatty liver disease are either completely resolved or substantially improved. Your risk of developing obesity related cancer is also reduced.

Long-term weight loss

Both the gastric bypass and sleeve gastrectomy operations lead to an average 50-70% excess weight loss at 3 years post-surgery. Patients lose most of their excess weight in the first year and can lose more weight over the next 6 to 12 months. Weight will usually stabilise after this. There can be some weight regain, but this is usually minor as long as you have put some lifestyle changes into practise as advised by the weight management team and the surgical bariatric team.

There is no amount of weight loss that is guaranteed. Long-term sustained weight loss and improvement in obesity-related health conditions will only occur with healthy eating and regular exercise. Bariatric surgery is best seen as a tool that makes these lifestyle changes sustainable. It is possible to regain all of your weight after surgery if you do not make the lifestyle changes that you have learnt about prior to surgery.

Preparation for surgery


A gastroscopy, also known as an OGD (a scope passed down the oesophagus, stomach and the first part of the small intestine) will be organised with the endoscopy department prior to either operation. This needs to be performed to assess the health of the oesophagus and stomach and to check for acid reflux, hiatus hernia and Barrett’s Oesophagus (a condition which can increase the risk of developing oesophageal cancer).

Some research indicates there is an up to 20% risk of developing acid reflux after a sleeve gastrectomy. Acid reflux can cause changes to the cells in the oesophagus known as Barretts Oesophagus. Further endoscopies will be required after a sleeve gastrectomy to look for evidence of Barretts Oesophagus.

Anaesthetic Review

Depending on your current health status, you may need an assessment with an Anaesthetist. This is to ensure that any existing health conditions do not pose a risk to you having an anaesthetic. The anaesthetist may carry out some additional tests or refer you for investigations, such as an exercise tolerance test or cardiac investigations. If you need to have an anaesthetic review, the reasons why will be explained to you.


Once you have a date for your operation, you will be sent an appointment to attend the pre-assessment clinic.

This is your final assessment appointment before surgery. At this appointment you will be seen by your Bariatric Specialist Nurse, who will confirm that there have been no changes in your health. You will have a medication review which will include giving you information on how to take your medication post-surgery. You may need to have some additional blood tests and have MRSA swabs taken.

During this appointment, your specialist nurse will give you the opportunity to practice how to self-administer your blood thinning injections, which you will need to have for 7 days post-surgery.

Liver Reduction Diet

Q: Why do I need to follow a pre-operative diet?

It is essential you follow a strict calorie controlled diet for three weeks prior to surgery. This will reduce the size of your liver and minimise the risk of complications associated with surgery. It will also ensure the operation can be done by keyhole/laparoscopic surgery. If your liver is too big your operation will be abandoned as it will not be safe to proceed.

By following a strict diet, your body reduces its glycogen stores (glycogen is a form of sugar stored in the liver and muscles). When you follow a very strict diet especially one that is low in carbohydrates, your body loses its glycogen stores and some water, which in turn shrinks the liver. Surprisingly the liver can replace its stores very quickly, so it is important that you follow the diet strictly. A single carbohydrate-rich meal shortly before your operation can undo all your good efforts and lead to difficulties during surgery.

This diet is not optional and is only recommended prior to your operation. Much of the weight lost on this diet is water. As a result you may become dehydrated so you need to drink more often than usual.
In addition to the diet remember to avoid alcohol and keep active e.g. walking or swimming.

Q: Why do I need to follow a pre-operative diet?

If you have diabetes and are treated with insulin or tablets (e.g. gliclazide, glibenclamide, tolbutamide) you may need to adjust your medication. Check your blood sugar levels more regularly to make sure that you do not experience ‘hypos’ (blood sugars below 4 and causing symptoms such as dizziness, sweating and shaking. Please contact the team if you are experiencing any problems).

If your diabetes is controlled by diet alone, you will not need to worry about your blood sugars becoming too low.

Please contact the hospital Diabetes Centre on Plymouth 01752 792963, who will be able to advise you about your medication.

Prior to you starting your liver reduction diet, we recommend you try the two different options; this is to see how your body might react with the diet whilst taking diabetic medication. One of the two options may be better for you than the other.

Q: What if I am a Diabetic?

The Diet

You must choose ONE and ONLY ONE of the following options

Option 1: Soup and Yoghurt Diet
This diet option is made up of no more than 400 calories of soup and 400 calories of yoghurt. The type of soup and yoghurt you eat is up to you, however you must check the nutrition label and ensure you do not exceed the recommended calorie amount.

Example of your daily intake:
Breakfast:        100 calorie yogurt
Snack:             100 calorie yogurt
Lunch:              200 calorie portion of Soup
Snack:              100 calorie yogurt
Evening Meal:  200 portion of soup
Snack:              100 calorie yogurt

Or you could have 4 cans of Weight Watchers® or other low calorie soups (under 100 calories per portion) and 4 low calorie yogurts (under 100 calories per pot), e.g. Muller Light®, Supermarket own brand diet yogurt or other low fat, low sugar varieties.
• 200mls skimmed milk for hot drinks
• Take a multivitamin and mineral tablet every day.

Option 2: A Meal Replacement Diet
This diet option is a nutritionally complete low energy liquid diet of no more than 800 calories a day.

Eg. Slimfast® (or a Supermarket own brand such as Tesco Slim or Morrison’s In Shape)
3 Slimfast® drinks (2 x level scoops each made with 250mls skimmed milk) or 4 Tesco Slim meal replacement drinks, not ready-made shakes, snacks or meal bars
• 200 mls skimmed milk for additional drinks

Fluid Intake on the Liver Reduction Diet

As well as the 200mls of skimmed milk for additional drinks you are allowed calorie free drinks to make up at least 2 litres of fluid.

Calorie free drinks include water, sugar free squash, herbal tea, tea or coffee (without sugar and using your 200mls milk allowance), Oxo or Bovril stock cube.

Spread drinks and food evenly throughout the day. Do not save everything for later in the day.

Drink at least 2 litres of fluid every day and drink more in hot weather.


Sweeteners are allowed. These include tablet sweeteners such as Hermestas®, Truvia®, Sweetex® and Silverspoon® and granulated sweeteners such as Stevia, Canderel® and Splenda®.

Hospital Admission

Day Zero: admission

You will be admitted on the morning of surgery unless you have specific medical problems that your anaesthetist and surgeon wish to monitor closely overnight. It is understood that you will have had a thorough shower prior to admission, and that you bring along everything you require for your hospital stay. Please do not bring anything valuable in with you. If you have any further questions please write them down and bring them with you to the hospital. Your admission letter will have the instructions about when you should stop eating and drinking on the morning of your operation

CPAP (Continuous Positive Airway Pressure)

If you currently use CPAP, please bring your machine with you to hospital and make sure your machine has had a recent service.


Don’t stop any medications unless told to do so. You will be advised at your Pre-Assessment appointment.

If you have type II diabetes we will usually stop your diabetic medications the day of surgery and they will not be restarted on discharge.

You will need to monitor your blood sugar levels regularly after surgery and also while you are on the liver reducing diet prior to surgery. It is not uncommon for patients to have to reduce the doses of their diabetic medications to avoid hypos whilst on the liver reducing diet.

During the admission process your surgeon, anaesthetist, bariatric nurse, admission nurse and theatre nurse will see you. This will mean that different people ask you the same questions. This is a safety issue, and although it can be frustrating, it is important. Use this time to ask any questions that you may have.

Once you have been admitted and changed into your theatre gown and TEDs (stockings to help prevent clots in the legs), you will wait in the preoperative area until the operating theatre is ready. A final check between the theatre staff and the admission staff takes place before you are taken into the operating room.

You will walk into the operating room and lie on the operating table, which is narrow and firm, and a blood pressure cuff, heart monitor and oxygen monitor will be attached to you so your anaesthetic team can monitor you closely throughout the procedure. Your anaesthetist will place a cannula (drip) into a vein and ask you to breathe some oxygen through a plastic facemask. Your anaesthetist will then gently send you off to sleep.

Recovery Unit

You will wake up in the recovery unit with all the monitoring still attached to you. Once you are awake and comfortable you will be transferred to the ward.

Further post-operative care:

Your nurse will record your vital signs regularly and give medications to control any pain or nausea.
You will be encouraged to do deep breathing exercises to keep your lungs healthy, and you will also be strongly encouraged to sit out in a chair. Early mobilisation is good for prevention of deep vein thrombosis (DVT). We will get you out of bed the same day as your surgery. You will also have TED stockings on as a further measure to prevent DVTs.

You can start to drink free fluids, sipped slowly, the evening of your surgery.

Day One Post Surgery


You will be seen early in the morning by various members of the team. The vast majority of patients will be discharged in the morning the day after surgery.

You need to maintain your fluid intake by having a cup or water bottle at hand and sip slowly and steadily. You will continue to be given blood thinning injections and wear TED stockings.

You need to drink a minimum of 1500mls of water per 24 hours.

Advice on discharge

You will be given medications to be taken home with you after discharge. These include:
• Multivitamins
• Calcium and Vitamin D
• Iron
• Analgesia for pain relief, usually for up to 2 weeks
• Anti-acid to reduce stomach acid, usually for 12 weeks
• Enoxaparin or a similar brand for prevention of pulmonary embolism
• Anti-sickness medication. Usually for 1-2 weeks
• All your regular medication

You will continue blood thinning injections for 7 days. The bariatric specialist nurse will teach you how to do this during your pre-assessment appointment.

Occasionally you may be prescribed a laxative for help with bowel movements.

You should continue taking your normal medications (apart from your diabetic medication) you were on before surgery, unless specifically told to stop. All medications can be taken as whole tablets. They do not need to be crushed or converted to liquid medication. We advise you to continue wearing your TED stockings for seven days post-op. This is to reduce the chance of blood clots forming in the legs Deep Vein Thrombosis (DVT) and can go to the lungs Pulmonary Embolism (PE).

Smoking can slow the healing of the staple lines, and can cause ulcers and bleeding. These complications can be life-threatening. You must not smoke or start smoking again following surgery.

It is also important that you refrain from alcohol post-surgery until you have got used to your new way of eating. When you do want to start alcohol again, do so only in moderation, it can have a more potent effect, and contains a lot of calories.

Recommended vitamin & mineral supplements

Multivitamin and mineral supplement should include:
• Iron
• Selenium
• copper
• zinc

One daily Forceval (soluble and capsule)
Two daily ‘over the counter’ complete multivitamin and mineral supplements.
Sanatogen A-Z complete®
Superdrug A-Z multivitamins & minerals®
Tesco Complete multivitamins & minerals®
Lloyds pharmacy A-Z multivitamins & minerals®

• 45-60mg daily
• 100mg daily for menstruating women

200mg ferrous sulphate, 210mg ferrous fumarate OR 300mg ferrous gluconate daily
200mg ferrous sulphate OR
210mg ferrous fumerate twice daily

Calcium and vitamin D

TheiCal D3 chewable once a day or Adcal D3 chewable forte twice daily

Vitamin B12

Intramuscular injections of 1mg Vitamin B12 three monthly, normally starting at 6 months following surgery

It is advisable to leave at least 2 hours between taking your calcium supplements and your Iron and multivitamin & mineral tablets to allow maximum absorption of nutrients.

Try to take your iron and multivitamin & mineral supplements with a good dietary source of vitamin C such as, a piece of fruit / vegetable to improve absorption.

Suggested supplement regimen

Morning                    Forceval Iron
Lunch time                Calcium and vitamin D
Tea Time (18:00)       Iron if you have to take it twice a day
Evening(Bed Time)   Calcium and vitamin D

Other medicines:

Thyroxine, if you take Thyroxine it is recommended to leave a gap of four hours before or after you take your supplements. It may be advisable to take it first thing in the morning.

Follow-up appointments

One week:

You will be contacted by phone around 1 week after your operation to check on your progress. Use this call to ask any questions you may have.

Six weeks: Appointment to see the Bariatric Dietitian or
Nurse and Consultant
Three months: Appointment to see the Bariatric Dietitian
Six months: Appointment to see the Bariatric Dietitian
Six months to 2 years post-surgery: (Plymouth Patients only)
Appointment to see the specialist nurse:
This is every 12 weeks for your Vitamin B12 Injection.
Out of area patients:
B12 injections will be done at your local GP surgery.

After six months if you are doing well, your follow up will be transferred to the weight management team. They will see you at 1 year and 2 years after surgery.

We work very closely with the weight management team, so if there are any concerns during your follow up with them they can refer you back to see a member of the surgical team.

Two years after your surgery you will be discharged from the weight management team and referred back to your GP. You will require annual blood testing by your GP to ensure you remain well. At this time your B12 injections will also need to be carried out at your GP surgery every 12 weeks for life.

If necessary your GP can arrange for you to see a member of the surgical team.

Recommended post-operative screening bloods tests

Blood test/procedure    HbA1c and/or FBG if diabetes pre-operatively   

Frequency     Monitor as appropriate                    

Blood test/procedure Lipid profile 

Frequency  Monitor in those with raised lipids

Blood test/procedure U+E, LFT, FBC, ferritin, folate, calcium, vitamin D, PTH

Frequency 3, 6, 12 months in first year then annually

Blood test/procedure Vitamin B12

Frequency  6 and 12 months in first year then annually

Potential complications

All surgery has risks, and as any stomach operation for obesity is considered major surgery, it has significant risks associated with it.

People have died from having operations for morbid obesity. It happens rarely, but the risk can never be taken away completely. If you are older, or you already have certain health problems related to your obesity, your risk may rise. Heart attacks after the operation or clots that form in the leg veins, which then pass to the lungs, can cause death in morbidly obese people after surgery. This risk is between 1 in 500 and 1 in 1000. Thorough precautions are taken during surgery and your hospital stay to minimise these risks, but they cannot be eradicated altogether.

Other problems that can occur after surgery include pneumonia and wound infections. Some of these are relatively minor and do not have a long-term effect on your recovery. Other complications may be more significant and require a longer hospital stay and recovery period. Antibiotics at the time of surgery, deep breathing exercises and early mobilisation after surgery are some of the measures taken to reduce the risks of these complications.

Other complications that could occur are listed below. This list is long, and although most patients have no complications, or minor complications only, please take note and ask your surgeon and team any questions that will help you to understand the risks associated with bariatric surgery.

During surgery

• A larger incision may need to be made because of technical difficulty with keyhole approach (open surgery)
• Bowel injury from insertion of keyhole instruments
• Bleeding from vessels or injured organs
• Injury to spleen. May require removal of spleen
• Injury to other organs. Examples: oesophagus, pancreas, liver
• Technical difficulty leading to change in operation strategy

After surgery

• Death. Rate between 1 in 500 to 1 in 1000
• Leak from staple lines or joins. Rate between 1 and 2 in 100. May require further surgery or lead to infection
• Bleeding. May require transfusion or return to surgery
• Infection. At keyhole incisions, or deep within the abdomen
• Sepsis. Severe infection that can lead to organ failure and death. This can lead to prolonged hospital stay and further surgery
• Pulmonary embolus, a blood clot in the lungs, can be fatal. Rate = 1%
• Deep vein thrombosis. A blood clot in the legs
• Pneumonia
• Respiratory failure. Inability to breathe adequately after surgery. This may require  support of breathing in an intensive care ward
• Heart attack or abnormal heart rhythm
• Stroke
• Pancreatitis
• Urinary tract infection
• Complications related to placement of intravenous and arterial lines. This includes bleeding, nerve injury or pneumothorax (collapsed lung)
• Nerve or muscle injury related to positioning during surgery
• Allergic reactions to medications, anaesthetic agents or prosthetic devices
• Colitis (inflammation of the colon). Usually due to antibiotics used in surgery
• Constipation

In the longer term

• Troublesome symptoms may include: abdominal pain, change in bowel pattern, tiredness, bloating, nausea or vomiting
• ‘Dumping syndrome’. This is an unpleasant feeling after eating sugary or fatty foods. Usual symptoms include anxiety, tremor and sweating
• Narrowing or ulcers (much higher risk in smokers) where the stomach and small bowel join. May require stretching with a balloon or, rarely, surgery. Ulcers can                perforate and cause peritonitis or bleed.
• Excessive or inadequate weight loss. Rarely requires further surgery
• Dehydration or imbalance of body salts. Usually from inadequate fluid intake, infrequently requires admission to hospital
• Gall bladder disease. Usually from gallstones that form during rapid weight loss, can require surgical removal of the gallbladder
• Hernias at the site of incisions
• Internal hernias. These can occur inside the abdomen because of the rearrangement of the bowel or scarring from surgery. This may block the bowel and is an ongoing risk that occurs in 1% of patients per year and then requires urgent surgery to correct
• Psychological problems that can include depression and adjustment disorder
• Relationship difficulties and rarely suicide
• Liver disease or failure. Can occur if there is underlying liver damage that is worsened by weight loss or surgery
• Nutritional deficiencies: This can occur if you do not take your supplements. Failure to do so can lead to some serious illnesses and disease
• Thinning of the bones (osteoporosis) can lead to fractures especially in women. Prevention requires lifelong dietary calcium supplements
• Hair loss from protein malnutrition

Pregnancy and Contraception

We recommend that if you are planning on becoming pregnant, you do not do so for at least 12 – 18 months after bariatric surgery. During this phase of rapid weight loss the body may not be getting all the essential nutrients it needs for a healthy pregnancy.
After gastric by-pass surgery the effectiveness of the oral pill may be reduced, therefore alternative methods of contraception will be needed. Precautions need to be taken even if you have been told you cannot have children as fertility often increases with weight loss.

If you do fall pregnant, please contact the bariatric team as soon as possible so that we can monitor you more closely.

Returning to Work

This is very individual and will depend on the nature of your job. If your job is very strenuous and involves heavy lifting it would be advisable to take up to 6 weeks off.


We recommend that you check with your insurance company. Most people will be able to drive 1-2 weeks after surgery. However, you will need to be able to perform an emergency stop safely.


Exercise and the support of others are extremely important to help you lose weight and maintain that weight loss following bariatric surgery. You can generally resume higher impact exercise and swimming 6 weeks after the operation; sooner than that, you can take walks at a comfortable pace and progress steadily. Exercise improves your metabolism, whilst both exercise and attending a support group can boost your confidence and stay motivated.

Nutritional information after surgery

After bariatric surgery you will need to make changes to your eating patterns. The diet after surgery progresses from a liquid diet (2 weeks) to a pureed diet (further 2 weeks) followed by a soft diet. This progression is designed to allow your body to heal. After about 6 weeks patients progress to eating three small meals a day of normal consistency food.

It is very important that you follow the diet progression to maximise healing and minimise the risk of complications.

Day zero (day of surgery)

• Regular sips of water
• Ice to suck

Day one

• 1.5 litre of water (slowly, as tolerated)
• Progress to sips of nutritious fluids by the afternoon

Day two - week two

• Free fluid diet (anything liquid at room temperature)
• Smooth soups, meal replacement shakes, tea/coffee, semi skimmed/ skimmed milk
• Include 1 pint of high protein milk over the course of the day (add 4 x dessert spoons of skimmed milk powder to 1 pint skimmed milk)

Must be low sugar containing fluids

Week two - week four

• Bariatric puréed diet
• Very small amounts of puréed/mashed food only. Initially this might only be 2-3 tablespoons of purée food progressing on to ½ – 1 ramekin sized portion

Aim to eat 5 very small puréed meals per day

Week four onwards

• Small meals of soft food that is high in protein and low in fat and sugar
• Aim for 3 small meals and two snacks per day but if this feels too much do not overeat as this will make you feel uncomfortable and may cause vomiting

General information

During all of the above stages and moving on for life, it is crucial that you:
AVOID liquids with meals (do not drink 30 minutes pre- and post-eating)
• Eat slowly using the 20/20/20 eating rule. Chew all food well and take time with your meals. If you try to eat too much too quickly or drink with meals, vomiting may occur
• Eating with a tea spoon is a good idea
• Drink between meals and aim for 6-8 glasses of fluid per day
• Ensure you have an adequate protein intake. We can advise you on an individual basis. Protein should be eaten before carbohydrates (starchy) foods
• Follow a general healthy diet, low in fat and sugar


• This is a very common problem in the first few weeks after surgery. It is almost always due to inadequate fluid intake. Keeping up with your fluid intake, and occasionally           using a gentle laxative such as docusate sodium will help with this. This can be bought over the counter or obtained via your G.P.

Pureed Diet

Foods allowed

High protein, low fat pureed foods:
Low fat yoghurt / Greek yogurt
Semi skimmed / skimmed Milk
Cottage cheese
Smooth Porridge eg. Ready break®
Mashed Weetabix®
Scrambled or poached eggs
Pureed meat/chicken/fish
Pureed/mashed vegetables/potato
Smooth soups
Pureed fruit
Raw fruit
Raw vegetables
Solid food
Food with lumps or bits

Foods to avoid

Raw fruit
Raw vegetables
Solid food
Food with lumps or bits

Low fat products

Cheese (high fat varieties)
Ice cream

Low sugar products e.g. Low sugar jelly
Low calorie drinks
Herbal teas

Squash with sugar
Soft drinks
Full sugar Jelly
Fizzy drinks

Modified diet

After your puréed diet move to a modified diet
Aim to have only 3 meals per day
You should be using a tea plate

Food group

Meat, chicken and fish

Foods allowed

Tender chicken, fish and meat in bite-sized pieces or minced. Wafer thin ham, turkey or chicken. Tinned salmon, sardines & mackerel, tuna in spring water

Foods to avoid

Hard or stringy meat, fat, chicken skin or gristle, fried meats

Food group

Milk and milk products

Foods allowed

Low fat milk, Cottage/ricotta cheese, Low fat yoghurt / Greek strained yoghurt

Foods to avoid

Ice cream, high fat cheeses, and full fat milk

Food group


Foods allowed

Soft fruits: peeled pears, apples, stone fruit, melon

Foods to avoid

Pips, skins, pith

Food group


Foods allowed

Well cooked vegetables: mashed, stir-fried, grilled or boiled
Introduce salads slowly

Foods to avoid

Tough or raw, stringy vegetables: green beans, corn, celery, broccoli stalks etc.

Food group

Breads and cereals

Foods allowed

Low fat crackers, rice, pasta, noodles, porridge, Weetabix, bran flakes

Foods to avoid

Doughy bread, muesli, high fat cereals

Food group


Foods allowed

Diluted juice, diet soft drinks and squash, herbal teas, coffee or tea with low fat milk

Foods to avoid

Soft drinks, energy drinks, milkshakes, full fat milk drinks, juice, fizzy drinks

Food group


Foods allowed

Artificial sweetener, herbs and spices, marmite, stock, low fat hummus, minimal oil when cooking. 

Foods to avoid

Sugar, chocolate, sweets, syrups, jams, butter, cooking oils, potato chips, high fat crackers, creamy sauces

Handy hints

• Introduce more solid foods after a few weeks, e.g. salads, lean tender meat and fish
• Avoid white bread. Instead try wholegrain crackers such as Ryvita or oat cakes
• Take care with bread, pasta, rice & noodles especially for the first three months after surgery. Try small amounts of toasted wholegrain or granary bread, crisp bread, crackers & potatoes instead.
• If eating out, order starter size meals
• Continue to eat regular meals and select healthy food options to optimize your continued weight loss
• Make sure that your meals are nutritious and include a balanced diet
• Look for <3g fat per 100g of food item
• Look for <5g sugar per 100g of food item

Food to include at each meal


You need to include low fat protein at each meal to ensure you maintain your muscle stores and lose fat stores, e.g.
• Lean red meat 2-3 x per week, e.g. lean mince
• Fish and chicken (no skin)
• Low fat dairy products, e.g. skimmed milk, low fat yoghurt, cottage cheese
• Tofu, beans and lentils, e.g. baked beans, hummus, kidney beans

Protein is very important; aim to fill half of your tea plate with protein. You should start each meal with it. Hair loss (temporary) can be a problem if there is inadequate protein in your diet.

Fruit and vegetables

• Aim to fill ¼ of your tea plate with vegetables / salad
• Fresh, frozen or canned vegetables.

   Carbohydrate / starchy foods

• Include some carbohydrate at every meal
• Allocate ¼ of a tea plate for carbohydrates (i.e. potato, bread, rice, pasta and cereals)
• If you can tolerate bread use wholegrain varieties. Toasted bread is often better              tolerated


• Use very minimal margarine or preferably none
• Avoid oil in cooking. Grill, bake, boil or stir fry or dry roast
• Avoid fatty meats, e.g. sausages, luncheon meat, salami


• Aim for 1.5-2L of fluid per day.
• Avoid full strength juice, squash, high calorie fizzy drinks, milkshakes

Ideally you should eat off a side plate (6 inch diameter). This will help to keep your portion sizes small. The diagram above of a bariatric side plate indicates the ideal portion size and food choices to make for optimum healthy weight loss and maintenance

Healthy lifestyle choices

There are several long-term habits that you should adopt to get the most out of your surgery. The first post-operative year is a critical time that must be dedicated to changing old behaviours and forming new, lifelong habits. You need to take responsibility for staying in control. Lack of exercise, poorly balanced meals, constant grazing and snacking, and drinking carbonated drinks are frequent causes of not achieving or maintaining weight loss.

To maintain a healthy weight and to prevent weight gain, you must develop and keep healthy eating habits. You will need to be aware of the volume of food that you can tolerate at one meal and make healthy food choices to ensure maximum nutrition in minimum volume. A remarkable effect of bariatric surgery is the progressive change in attitudes towards eating. Patients begin to eat to live; they no longer live to eat.

Support Groups

Weight Management run a patient led support group for patients before and after bariatric surgery called the Weigh Forward Group. Please ring Weight Management on Plymouth 01752 434623 to confirm time and venue.

Who to contact

Claire Woods, Bariatric Nurse Specialist
Rachel Griffin, Ciara Caleshu, Bariatric Dietitians

Email: plh-tr.DerrifordBariatrics@nhs.net

Direct line 01752 431724 – this is an answer phone. Please leave a message and you will be called back as soon as the message is picked up.

If your query is urgent, phone Derriford Hospital switchboard on 0845 155 8155 and ask them to bleep the Bariatric Nurse Specialist.

If your problem is very urgent you will need to attend the Emergency Department (Casualty) at Derriford Hospital.


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