Problem Solving after Bariatric Surgery

Bariatric surgery involves making changes to your digestive system to help you lose weight so perhaps it is not uncommon to experience changes in how you tolerate foods. It can take several weeks or months to get used to the new way of eating and drinking and some people who have had bariatric surgery can develop side effects. Below is a list of the more common problems people face after weight loss surgery, what causes them and what you can do to alleviate or prevent them.




  • Constipation is a common issue, particularly in the early stages following surgery. 
  • Try to drink 8-10 glasses of fluid a day (2-2 1/2 L or 3 1/2-4 pints) to help you stay hydrated and prevent constipation.
  • Try to sip fluids slowly throughout the day as it may feel uncomfortable if you try to drink too much too quickly. 
  • Moderate intensity exercise can also help to get the bowels moving so increase your activity levels as appropriate. Try to walk every day.
  • increase the amount of fibre in your diet (fruits, vegetables, wholegrains). See your dietitian for further ideas.



Diarrhoea is less common after surgery. In rare cases complications from gastric bypass can result in diarrhoea but these problems are usually related to diet.

  • Eat slowly. Stop eating when full and avoid drinking with meals.
  • Avoid sugar, fat, alcohol and spicy foods.
  • Limit the amount of artificial sweeteners in foods because in some people, these can also cause diarrhoea.
  • Limit drinks containing caffeine to 2 cups per day.
  • If you have persistent diarrhoea following surgery talk to your bariatric team.



Heartburn, or acid reflux, results from the stomach contents flowing back up into the oesophagus, or gullet, and sometimes all the way into the mouth. Gastro-oesophageal reflux disease (GORD) is chronic heartburn which flares up easily and often after eating. Many patients who have had bariatric surgery find the symptoms of acid reflux or GORD improve following weight loss. This is particularly so after the Roux-en-Y gastric bypass (RYGB). However, some patients who have had a gastric sleeve will find that they develop new symptoms of acid reflux. 

  • Sometimes, there are certain foods which may trigger acid reflux so by trying to identify which food or drink triggers your heartburn and avoiding them you may be able to control the problem. Common food and drink that may trigger heartburn include coffee, tea, caffeinated fluids, chocolate, spicy foods and alcohol.
  • Eating too much and too quickly can also trigger acid reflux.  Try to eat slowly and stop eating as soon as you feel full.
    • Try not to eat just before going to sleep. Leave at least 3 hours between your last meal and bedtime.
    • Stop smoking.
    • Avoid aspirin and other anti inflammatory medication such as Ibuprofen and Voltarol.
    • If you have changed the way you eat and you still suffer from reflux then speak to your doctor who can prescribe medication to control your symptoms.


  •  In a few cases where medication and dietary changes are not effective then conversion to a gastric bypass may be necessary for permanent relief. 




Stomach discomfort is not uncommon if you have recently had bariatric surgery. The feeling of fullness you experience after eating before surgery will feel different from the feeling of fullness you will experience after surgery, so learn to recognise when you are full. The following tips will help minimise the discomfort:

  • Don’t eat past the point of fullness.
  • Avoid foods that you have not tolerated well.
  • Chew all food thoroughly
  • Eat slowly – allow 20- 30 minutes per meal. Relax and choose pleasant, quiet surroundings when you eat.
  • Keep drinking fluids but do not eat food and drink liquids at the same time. It is natural that we would drink with our meal. However following bariatric surgery mixing liquids with food can cause discomfort. Try to drink about an hour before your meal and about 30 minutes or more after your meal.
  • Try nibbling on 1-2 low-fat crackers when you first feel nauseated. Make sure they are very soft before swallowing them. Sometimes flat-diet ginger ale, herbal tea or broth also help.
  • Avoid spicy or acidic foods (e.g., citrus or tomato juices).
  • Avoid foods high in fat or sugar
  • There are uncommon complications associated with surgery, particularly RYGB, such as internal hernia or strictures that can cause recurrent abdominal pain and vomiting. Please see your surgeon if you develop severe abdominal pain, particularly with vomiting and inability to keep fluids down.



Dizziness is common after bariatric surgery. It can range from mild light-headedness to feelings of faintness and weakness. There are many factors that can cause dizziness after surgery such as nutritional deficiencies, electrolyte imbalance, dumping syndrome but most commonly it is due to low blood pressure. When you sit or stand up your blood pressure drops momentarily, making you feel dizzy. It may be particularly problematic after meals. You can take some practical steps to prevent it. 

  • Make sure you are drinking enough fluids as a common trigger is dehydration. 
  • Try to drink  8-10 glasses of fluid a day
  • Add salt to your foods.
  • Rise slowly, particularly if you been sitting for a while or after eating a meal.
  • Make sure you are having your blood tests done on a regular basis and you are taking your multivitamin and multimineral supplements.
  • Speak to your doctor if your symptoms persist.



Early dumping syndrome has symptoms which typically occur within the first hour after a meal and is caused when food or drink high in sugar or starch move suddenly into the small bowel. It can also occur if fluids are taken too soon following a meal. 

Symptoms include abdominal bloating, cramps and pain, sweating, nausea and vomiting, heart palpitations, dizziness or fainting and diarrhoea.

Late dumping syndrome is a result of reactive hypoglycaemia. Following weight loss surgery carbohydrate is quickly absorbed into the bloodstream. Sometimes the pancreas produces too much insulin to deal with the rapidly absorbed sugar resulting in a low blood sugar level. Symptoms usually develop 1-3 hours after a meal and include: heart palpitations, sweating, fainting, fatigue, confusion, hunger and tremors.


Some examples of foods that may lead to early or late dumping syndrome include chocolate, sweets, puddings and desserts and full sugar drinks.

Tolerance levels vary from person to person, however these foods should be kept to a minimum due to their overall calorie content.

To prevent early or late dumping syndrome:

  • Eat little and often – 3 small meals a day and 2-3 small nutritional snacks a day.
  • Combine protein with complex carbohydrates. This will slow down the absorption of sugar.
  • Minimise or avoid high sugar foods within your diet. Choose low glycaemic index carbohydrates.
  • Do not drink with food. Avoid drinking 30 minutes before a meal and one hour after a meal.
  • Reduce consumption of caffeine or alcohol containing drinks



Everyone is unique. Although most people lose between 50 and 70% of their excess weight following a sleeve gastrectomy or a Roux-en-Y gastric bypass it is estimated that 15-30% of patients do not achieve satisfactory weight loss or will regain weight. The degree of weight loss is affected by age, physical activity level, dietary discipline and our metabolic rate. Some people lose more weight than expected while some lose less. It is difficult to predict. If you are not happy with your weight loss:

  • Use a small plate to control portion sizes.
  • Eat slowly. Chew each mouthful 20 times and take 20-30 minutes maximum to complete a meal.
  • Do not leave food on the plate to return to a later get rid of it.
  • Always start with the protein, followed by vegetables or salad and leave the carbohydrates for last.
  • Do not add lots of gravy or sauces to help food get down as this will allow you to eat more food than you need.
  • Stop eating before you feel full.
  • Practice mindful eating  – concentrate on your meal rather than watching television and working while eating.
  • Avoid drinking sweetened beverages such as fruit juice, cappuccino and fizzy drinks.
  • Be as active as you can.
  • Weigh yourself on a weekly basis.
  • Keep food records and write down everything you are eating and drinking. Show these records to your dietitian and discuss your diet and eating habits with them.
  • Be aware of your eating patterns. Are you snacking frequently? Remember, the surgery will only prevent you from eating too much at one time, but it does not prevent you from gaining weight through constant snacking. 
  • Make sure that you are only eating when you are hungry. If you feel that you are eating for emotional reasons as well then please speak to your bariatric team.



Following weight loss surgery the nutrition plan is designed to provide a balanced diet of high quality protein, complex carbohydrates and healthful fats. Nutritional deficiency can cause hair loss, tiredness and dizziness. In severe cases it can also cause poor wound healing, painful bones and brittle nails and numbness or burning in the feet. All this can be prevented by:

  • Ensuring you have enough protein with every meal. 
  • Ensuring you are eating enough fruit and vegetables.
  • Taking all your multivitamin and multimineral supplements, including iron, calcium, vitamin D and B12 as prescribed by your doctor



It is quite unusual to lose too much weight following weight loss surgery. Your weight loss tends to stop 12-18 months following surgery.  

  • Monitor what you eat to identify if you are eating enough and review your food records with your dietitian. Increase the amount of food in your diet if necessary. Your dietitian will help you with this.
  • Arrange to see your doctor. There might be a medical reason for the weight loss.



  • Surgery is a significant life event and despite all the positive results, making changes can be stressful and emotional. Emotional fluctuations are completely normal and tend to stabilise over time. Realise that you are going through an adjustment period with your eating patterns and adapting to your body. 
  • Food is an important part of our life. We often turn to food in times of celebration, sadness, for reward and for comfort. You might need to learn new coping methods besides eating. Consider finding hobbies and different activities to turn the focus away from food.
  • If you are taking an antidepressant before surgery then please do not stop taking it without seeing your doctor.
  • It is important to ask for help if you find that you are having difficulty adjusting to the many changes after surgery. Seek support from family, friends, support groups and/or professionals. Talk to successful members of the support group to see how they handled feelings of frustration and discouragement.
  • Remember why you had the surgery in the first place. Pay attention to your body when it is getting healthier and stronger.
  • Don’t neglect your physical health – it affects your mental attitude. Be sure to eat a well-balanced diet, take your vitamins and get enough sleep.
  • If you find that your mood is lower than usual, especially if you have thoughts of harming herself, please make an appointment as soon as you can talk things over with your doctor.



It is normal for most patients to experience hair loss in the first year after surgery due to the physiological stress created not only by the surgery but the rapid weight loss that follows. Hair loss is usually temporary. You can reduce the degree of hair loss by: 

  • Having a well balanced diet with sufficient amounts of high-quality protein. 
  • Remember to take your multivitamin and mineral supplements regularly.



This varies from person to person and depends on your age, physical activity level, degree of weight loss, whether or not you are a smoker, your genetics and other factors. Most patients who lose 40 kg or more will have some loose or saggy skin. The main problem areas tend to be the tummy, arms and thighs. Many patients may opt for surgery to remove the excess skin. It is recommended that you wait at least 6 months after your weight has stabilised before you are evaluated for surgery. Removal of excess skin is not usually covered by health insurance or the National health service.



In summary, the benefits of bariatric surgery far outweigh the risks in patients with severe obesity and with obesity related complications. However, surgery can pose some risks and side effects. Attending regular follow up appointments with your dietician and doctor is important to make sure that you are adjusting to your procedure, not suffering from nutritional deficiencies or other unwanted effects of surgery. Making permanent healthy changes to your dietary behaviour and taking your vitamin supplementation will help ensure the long-term success of bariatric surgery and reduce the risk of late unwanted effects. 


BY Dr Mohgah Elsheikh