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Your pre-operative liver shrinking diet

Pre-op diet patients
Pre operative diet

It is important that you follow a strict diet before your gastric bypass surgery. By following this diet you reduce the chance of experiencing a complication with your surgery.

What is the diet?

You need to follow a low calorie diet. The calorie intake should be between 800 to 900 calories a day.

Why do you need to follow the diet?

The purpose of the diet is to shrink your liver in preparation for surgery. The diet reduces the amount of glycogen (storage form of carbohydrate), water and fatty deposits in the liver, which reduces the liver's overall size. 

Is the diet optional?

The diet is compulsory. This means it is extremely important you follow it. 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.

How long should you follow the diet for?

It can vary depending on your BMI. If this applies to you we will normally apply the following scale.

  • If your BMI is 32-40 follow the pre-op diet for 5-7days
  • If your BMI is 40-50 follow the diet for 2 weeks
  • If your BMI is 50-60 follow the diet for 3 weeks
  • If your BMI>60 follow the diet for 4 weeks

Your surgery box
Your surgery box

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

Below is an example of what you could be enjoying while you're preparing for surgery. We also offer the Weight To Go surgery box to help our patients manage their liver shrinking diet.

Breakfast (150-200 kcal)

Select one from the list below

  • 1 Weight to Go porridge served with a handful of blueberries

  • 1 wholegrain toast with scrambled egg    

  • 0.5 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 (80 kcal)

Select one from the list below

  • 1 portion of fruit

  • Low-fat yogurt

Lunch (150-200 kcal)

Select one from the list below

  • 1 Weight to Go soup served with a side salad

  • Salad with chicken breast / tuna / beans

  • 1 brown toast / 2 crisp breads with deli meat / tuna / low-fat cottage cheese

Mid-afternoon snack (80-100 kcal)

Select one from the list below

  • 1 Weight to Go shake chilled into a mousse / iced dessert

  • Raw veg with a low-fat dip

  • Low-fat yogurt

Dinner (300 kcal)

Select one from the list below

  • 1 Weight to Go soup served with a portion of veg

  • 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

IMPORTANT: 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. 

Preparing Your Shakes
Preparing Your Shakes

Your Surgery Box- how to prepare

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. 

Other Pre-op Information

preparing for surgery

Surgery Preparation 

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 If you have any questions at all, please contact us 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.