Life after weight loss surgery 

It's very important to stick to your recommended diet plan after surgery.

Diet plans can differ between specialist centres and depend on your individual circumstances. However, most people will be given a plan similar to the ones described below.

Diet after a gastric band operation

Your diet after a gastric band operation will progress over three main stages:

  • In the first four weeks after surgery, you'll only be able to drink liquids and eat small amounts of puréed food, such as mashed potato.
  • In weeks four to six, you can have soft food, such as chicken.
  • After six weeks, gradually resume a healthy diet based on eating small amounts of nutritional food.

Each stage is discussed in more detail below.

First four weeks

It's important that any food you eat during this period is puréed. Attempting to eat solid foods at this stage could put pressure on the band and damage it.

Puréed food has the same texture and consistency as baby food. You can purée food using a food processor, hand-held blender or potato masher.

Additional fluids, such as sauces or water, may be required to soften some types of food.

Aim to eat small portions four to five times a day. A portion is around 100g, or five to six tablespoons of food. Eat all your meals slowly, taking small mouthfuls.

Stop eating as soon as you feel full. Because of the position of the band, you'll probably experience a feeling of fullness or tightness in your chest rather than in your stomach.

Aim to drink around 1.5 litres (2.5 pints) of water a day. Drink small glasses, around 100-200ml, between meals, but never with your meals.

If you experience repeated episodes of vomiting after eating, it may be a sign you're eating too much or that your band needs to be adjusted. Contact your surgical unit for advice.

Weeks four to six

Continue to eat a similar diet as you did for the first four weeks, but your food no longer has to be puréed, although it should be soft.

For example, you could eat:

  • wholewheat breakfast cereals mixed with milk
  • porridge
  • mashed potatoes and melted cheese
  • soup
  • yoghurt
  • rice pudding

After six weeks

After six weeks, you'll be ready to adopt a long-term diet that you'll need to stick to for the rest of your life. Your band should now be adjusted correctly, so you should need to eat much less to satisfy your appetite.

While weight loss is an important goal of your diet, don't neglect the nutritional content. See the box at the bottom of this page for more information on what makes a healthy, balanced diet.

The British Obesity Surgery Patient Association (BOSPA), a charity for people who could benefit from surgery, has six golden rules you'll need to follow to get the maximum benefit from your gastric band:

  • Only eat three meals a day.
  • Avoid snacking between meals. If you're following your recommended guidelines, there's no reason why you should feel hungry between meals.
  • Eat solid food. While soft foods may be easier to digest, they usually contain more carbohydrates and fat, and make you feel less full than solid foods.
  • Eat slowly and stop eating as soon as you feel full. Cut your food into very small chunks, then chew each chunk as many times as possible before swallowing. Stop eating once you feel a sensation of fullness or tightness in your chest. Overeating or eating too fast could cause unpleasant symptoms, such as pain and vomiting.
  • Don't drink during meals. This can flush food out of your stomach pouch and make you feel less full. Avoid drinking fluids 30 minutes before a meal and for an hour afterwards.
  • Avoid drinking high-calorie drinks, such as cola, alcohol, sweetened fruit juices and milkshakes. These types of drink quickly pass out of your stomach and into your small intestine, increasing your calorie intake. Ideally, drink water or zero-calorie drinks, such as diet cola or diet lemonade.

Diet after a gastric bypass

The progression of diet stages after a gastric bypass is broadly similar to those after a gastric band:

  • In the first week after surgery, only drink liquids (this doesn't include puréed food).
  • In weeks two to four, you can eat puréed food in the same quantities (100g) and frequencies (four to five times a day) as described above.
  • In weeks four to six, you can eat soft food.
  • After six weeks, gradually resume eating a healthy diet.

The golden rules above also apply to your diet after a gastric bypass.

However, you need to be aware of several additional issues.

Firstly, you'll need to avoid eating food high in sugar, such as chocolate, cakes, sweets and biscuits. This is because your bypass affects how you digest sugar, and any sugar you eat will trigger your body to produce high levels of insulin.

The excessive amount of insulin can cause a number of unpleasant symptoms that are collectively known as dumping syndrome. Symptoms of dumping syndrome include:

  • nausea
  • abdominal (tummy) pain
  • diarrhoea
  • light-headedness

Secondly, you'll need to take daily vitamin and mineral supplements, as your small intestine will no longer be able to digest all the vitamins and minerals your body needs from your diet.

The dosage and type of supplements can vary from case to case, but most people are required to take:

  • a multivitamin supplement, which contains a combination of different vitamins
  • a calcium supplement (the body requires calcium to maintain healthy bones)
  • an iron supplement

Diet after other types of weight loss surgery

The recommended diet after other types of weight loss surgery is likely to be similar to the advice above.

Your specialist centre can provide more detailed advice.

Exercise after weight loss surgery

Losing weight and then maintaining a healthy weight doesn't simply involve reducing the amount of calories you eat. Burning calories while exercising is also important.

Regular exercise has additional health benefits other than weight loss. These include reducing your risk of developing heart disease and some types of cancer, and boosting your self-esteem and wellbeing.

You'll probably be given an exercise plan that starts gradually with low to moderate amounts of physical exercise, such as 10 minutes a day, then gradually increasing.

The exercise should be intense enough to leave you feeling out of breath and getting your heart beating faster.

Recommended types of physical exercise include:

  • activities that can be incorporated into everyday life, such as brisk walking, gardening or cycling
  • supervised exercise programmes
  • activities such as swimming, walking (where you aim to walk a certain number of steps a day) and stair climbing

Chose physical activities that you enjoy as you'll be more likely to continue doing them.

Further information

Read more about fitness, including information on:


A healthy balanced diet

What you eat is just as important as how much you eat after your surgery.

Generally, your diet should contain a healthy mix of the five main food groups:

  • protein – ideally low-fat protein foods such as chicken, fish, eggs and beans
  • dairy products – such as skimmed milk and low-fat cheese and yogurt
  • carbohydrates – such as bread, potatoes and cereals
  • fruit and vegetables – ideally five portions a day
  • fats – using a small amount of olive oil when cooking should provide your body with all the fat it needs

Your specialist centre can give you more advice on how best to meet your individual nutritional needs.

Page last reviewed: 26/03/2015

Next review due: 26/03/2017