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Before your gastric bypass operation - planning for success

This section covers what you can do in preparation for your procedure to get your weight loss off to the best possible start.

Support and advice

You may have questions / concerns about your procedure and how your life is about to change. This is completely natural and there are many ways that we can help to answer these questions and reassure you:

Telephone support

We are here to help whenever you need us so whatever your question, please call us on 0121 693 4488

  • Our Patient Care team can answer general questions regarding your booking

  • Our Bariatric Nurses can answer medical questions, for example on medication, how to use the pre-operative diet etc.

Facebook support forum

This secret group is for Healthier Weight patients only and is a great source of support, advice and motivation from people who have been through the same experience. You will see posts from new patients like yourself and experienced patients years further down the line. It is a great place to share your questions, feelings, successes (and struggles) in total confidence.

Note: this is a secret group so posts will not show in your timeline and your membership to the group will not be visible to anyone.

You will receive an email invitation to join the group following your procedure. This email invite will come from facebook so please check your junk / clutter folders if you can't find it in your inbox. If you don't receive it within a week of your procedure, please call us.

Nutritional food for your pre-op diet

Before bariatric surgery you need to follow a low-carbohydrate 800-900 calorie diet to reduce the amount of glycogen (storage form of carbohydrate), water and fatty deposits in the liver and thus reduce the liver’s overall size. The purpose of this is to allow the surgeon to safely move the liver aside during the operation which will reduce the risk of complications associated with surgery. This pre-op diet will also help with the transition between your normal diet and the 2 weeks post-op liquid diet that you will have to follow. We advise you take 1 multivitamin tablet and 1 iron tablet per day) during your pre-op diet to ensure good concentrations of vitamins and minerals which are important for post-op recovery and healing. The pre-op diet is not optional and should only be followed before surgery.

How long will I need to follow the pre-op diet for?

This will depend on your BMI (see guide below) but a pre-op diet of 5 days is generally required. You may have been advised at consultation to follow the diet for longer so please follow as recommended.

  • BMI 40-50: follow the diet for 2-3 weeks
  • BMI 50-60: follow the diet for 3-4 weeks
  • BMI >60: follow the diet for 4-6 weeks    

The pre-op diet has to be a nutritionally balanced low-fat, low-carb and moderate protein diet. Therefore we highly recommend you follow the pre-op Weight to Go diet (shown in bold below). However, if you wish to prepare your own food, you can have some Weight to Go products, for example the shakes, and combine them with some of the meal options listed below. Do not be tempted to have a large meal the day before surgery as this will reduce the liver reducing effects of the diet.

Note: The pre-operative diet is not optional, it is mandatory. If the diet is not followed the surgeon may refuse to operate on you. A large liver may cause the surgeon to abandon the operation. Do not be tempted to have a large meal the day before surgery as this will reduce the liver reducing effects of the diet.


Sample Pre-operative Menu: Minimum of 5 days before surgery

(using Weight to Go)

  • 1 Weight to Go porridge served with a handful of blueberries
Other breakfast options (170 - 200 kcal)
  • 1 wholegrain toast with scrambled egg    

  • 1.5 Weetabix with 125ml skimmed milk and half a banana/ strawberries

  • 30g oats / bran flakes / All-Bran etc with 125ml skimmed milk and half a banana

Mid-morning snack (using Weight to Go)
  • 1 portion of fruit
Other snack options (80 kcal)
  • 1 portion of fruit
  • Low-fat yogurt
(using Weight to Go)
  • 1 Weight to Go soup served with a side salad
Other lunch options (150 - 200 kcal)
  • Salad with chicken breast / tuna / beans
  • 1 brown toast / 2 crisp breads with deli meat / tuna / low-fat cottage cheese
Mid-afternoon snack (using Weight to Go)
  • 1 Weight to Go shake chilled into a mousse / iced dessert
Other snack options (80 - 100 kcal)
  • Raw veg with a low-fat dip
  • Low-fat yogurt
(using Weight to Go)
  • 1 Weight to Go soup served with a portion of veg
Other dinner options (300 kcal)
  • 100g very lean meat (e.g. chicken breast without skin) / grilled white fish / pulses (e.g. lentils & beans) with a portion of veg or a side salad

Ensure you drink at least 2 litres of fluid per day

Tips: For extra flavour you can add salt, pepper, herbs, spices, mustard, lemon / lime juice, vinegar, stock cubes, garlic, vanilla etc. Do not add any butter, oil or cream to your veg. A portion of fruit is: one piece of fresh fruit e.g. apple / banana; 2 small fruits e.g. plums / apricots; 1 small glass of fruit juice; 1 tbsp dried fruit; a handful of grapes / cherries

Your pre and post-op surgery box

How to prepare your Weight to Go shake

Preparing Weight to Go Shakes

For the best, creamiest results we recommend mixing with an electric jug / handheld blender. If you don’t have a blender, mix your shake by hand or in a shaker.
Ice cold shake: Blend with 260mls cold water or 200mls cold water and 4-6 ice cubes for a thicker shake.

Filling smoothie: Add a handful of fresh/frozen berries or a banana and blend
For a satisfying hot drink: Add 200mls hot (NOT boiling) water and blend on low speed for 5-10secs. All shakes can be made into hot drinks but chocolate and vanilla are the most versatile eg make a vanilla shake with black coffee for a café latte

How to prepare your porridge

Preparing Weight to Go Porridge

Porridge makes a wholesome breakfast or a filling snack any time of the day. Weight to Go Porridge Oats are already sweetened but you can add calorie free sweetener to taste.

Microwave: Mix with 120mls cold water in a bowl and microwave on full power for 90 seconds. Stir then leave for 1-2 minutes before consuming.

Hob: Empty sachet contents into saucepan and mix with 120mls cold water. Heat gently on low heat until piping hot. Stir and serve. 

Recipe tips: For something a bit different, porridge can also be used to make oaty pancakes or added to a chocolate shake to make oaty hot chocolate. View recipe ideas at Weight to Go

How to prepare your Weight to Go soup

Preparing Weight to Go Soups

Our range of soups make a warm, comforting lunch and are easily prepared at home or on the move.

Mix with 220mls boiling water in a bowl or mug. Stir or whisk until fully mixed then leave for 4-5 minutes before consuming.


There are two steps in this pre-operative assessment, both of which are required to enable your procedure to go ahead:
  • Hospital assessment - you will be given an appointment to attend for a medical assessment, usually at the hospital at which your procedure will take place. At this appointment, bloods will be taken and a general medical screening will be undertaken to discuss medical history, medication etc and to take readings such as height, weight and blood pressure.

  • Telephone assessment - you will receive a telephone call from one of our Bariatric Nurses to complete a final pre-operative admission assessment. This information is essential to complete your booking and allow hospital admission.



Going to hospital

It is natural to be nervous prior to your procedure and being fully informed and planning in advance can help to alleviate those nerves. The following is a list of questions that have have been frequently asked by patients in the past. If your question is not listed here or you want any further information, please call us on 0121 693 4488.

Can I eat or drink before my procedure?
You will be asked to eat and drink nothing from midnight on the evening before your admission. However, if your procedure is not until the afternoon, you may be allowed a light breakfast in the morning (to be confirmed in your pre-op call). Depending on admission time, the bariatric nurse will advise you accordingly.

I haven’t received admission information. What time do I come in?
You will receive communication from the hospital at which you are due to have your procedure, which will provide an admission time. If you have not received this letter within three days of your procedure, call the team on 0121 693 4488.

Do I take my medication on the day of my procedure?
You will be asked to take your regular medication on the day of your procedure (with a very small amount of liquid). However, some medication may require specific management and you will be advised about this before admission. In some circumstances (e.g. if you are diabetic) you may be asked to attend hospital in advance of your procedure for tests and to adjust your medication.

What do I need to take to hospital?

  • Regular medication in its original packaging
  • Your continuous positive airways pressure (CPAP) machine if you use one
  • Nightwear
  • Essential toiletries
  • A dressing gown and slippers
  • Comfortable clothes to travel home in (e.g. a skirt or trousers with a loose, elasticated waist)

What happens when I’m admitted?
You will be taken to the ward where the nursing staff will complete the standard admission forms and carry out baseline observations (pulse, temperature, blood pressure etc.). You will also be fitted with a pair of anti-embolism (TED) stockings which you will be required to wear throughout your hospital stay and for 10-14 days after surgery. Unless a blood test was completed in advance of your surgery, bloods will also be taken. Not all consultants discharge patients with anti-embolic stockings.

You will be seen by your consultant who will go through the consent form with you. This is to confirm your understanding of the procedure, together with the risks and benefits. If you have any concerns or questions, please ensure you raise these with your consultant before signing the consent form.

Do I need someone to take me home?
After a general anesthetic we ask you not to drive or operate machinery within 72 hours. If you have driven to the hospital, please ensure there is someone to drive you home.  Please be aware that if you choose to drive despite this advice, your car insurance company may not cover accidents that occur during this time.

I have received a bill from the hospital. What do I do?
If you have received a bill from the hospital which you are not expecting, please contact the Healthier Weight Administration Team immediately on 0121 693 4488. In most cases you should not receive a bill for anything that has been included in your surgery package. In very rare occasions this may happen and if so please accept our apologies. Extras such as newspapers, visitors’ meals etc. are not included in the package.


 If you have any questions at all, please contact us on 0121 693 4488

Got a question? Call our team today on 0121 693 4488
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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.