Many people have heard of surgical treatments for obesity. What happens before and after them, and what you need to watch for, especially with eating, is often less clear. This article gives an overview.
Research shows that obesity causes serious health problems, lowers quality of life and even raises the risk of death. Excess weight brings long-term conditions, from heart disease and high blood pressure to type 2 diabetes and cancer. For people who do not lose weight despite diet and exercise, bariatric (weight-loss) treatments may be an option. The gastric sleeve and gastric bypass are among the most commonly performed operations.
Surgical treatments
These operations may be considered for people with obesity when non-surgical methods have not worked well enough.
- Gastric sleeve (sleeve gastrectomy): the stomach is made about 80% smaller, which limits how much you can eat at one time. It does not reduce the absorption of nutrients. You feel full after small amounts, and this feeling lasts for a few hours. The removed part of the stomach also produces the hunger hormone ghrelin, so less of it is released.
- Gastric bypass: the stomach is reshaped into a small pouch and connected to the small intestine. The aim is to reduce both the amount of food and the absorption of fat and calories.
Who can have surgery?
- people with a BMI (body mass index) above 40 kg/m²,
- men who are 45 kg and women who are 35 kg above their ideal weight,
- people with a BMI of 35 kg/m² or more and obesity-related conditions such as type 2 diabetes, sleep apnoea or heart disease,
- people with a BMI above 30 kg/m² with type 2 diabetes or severe metabolic problems.
Bariatric surgery can help reduce or resolve these obesity-related conditions:
- type 2 diabetes,
- high blood pressure and high cholesterol,
- sleep apnoea,
- heart disease.
Risks
Even though some of these operations are done by keyhole (laparoscopic) surgery, all bariatric operations are major operations. Possible risks include:
- infection,
- embolism (a blood clot that blocks a vessel),
- pneumonia,
- ulcers,
- gallstones,
- a feeling of food getting stuck if it is not chewed well enough,
- nausea or vomiting,
- malnutrition.
Weight-loss surgery is not a solution on its own. Its effect depends on making the advice on diet and exercise a lasting part of your daily life.
Before the procedure
- Your doctor will explain the procedure and answer your questions.
- You will be asked to sign a consent form. Read it carefully and ask if anything is unclear.
- As well as a full medical history, you will have a physical examination, and you may need further tests.
- If you drink alcohol, you will be asked to stop before the procedure.
- You must not eat or drink for eight hours during the night before the procedure.
- Tell your care team if you are sensitive or allergic to any medicines, latex, iodine, tape or anaesthetic drugs.
- List all the prescription and over-the-counter medicines and herbal products you take.
- If you have a bleeding disorder or take blood-thinning (anticoagulant) medicines, be sure to talk to your doctor about it.
After surgery
In hospital
- After weight-loss surgery you will usually stay in hospital for a few days. During this time you will be given pain relief if you need it.
- You will be encouraged to move as much as you can in bed, to get up and, as you get stronger, to walk around. Moving early is important to prevent blood clots.
- At first you will be fed through a vein. Your diet is then built up step by step, depending on the procedure (see below).
- Because your digestive system has been changed, you will need to take supplements to make up for missing nutrients.
At home
- Keep the wound area clean and dry. Your doctor will give you clear instructions about showering and bathing.
- The cut and your stomach muscles may hurt, especially when you breathe deeply, cough or strain. Only take the pain relief your doctor recommends.
- Keep doing the breathing exercises you were shown in hospital.
- Increase your physical activity gradually. It may take a few weeks before you are back to your usual level.
- You may be asked not to lift heavy objects for a few months.
- You may feel tired in the first month after the operation.
Contact your doctor straight away if you have:
- a fever or chills,
- redness, swelling or bleeding around the cut,
- increasing pain around the cut.
Eating after treatment
After bariatric treatment you will need a new way of living and a new way of eating. You should learn the rules of your medical diet from an experienced dietitian.
After a gastric sleeve
- Your diet is built up in stages. This supports healing and helps you return to healthy eating habits. You eat small portions often.
- For the first two weeks you have clear liquids. This diet helps prevent problems such as diarrhoea, constipation and dehydration, and gives your body time to heal. Protein is very important: to avoid losing muscle while you lose weight quickly, you should have at least 60 g of protein a day. A multivitamin is recommended to help prevent problems such as hair loss, sleep problems and tiredness.
- In the third week you move on to puréed food, made in a blender. You should have 60 to 80 g of protein a day and make sure you drink enough.
- In the fourth week you move on to soft food. You learn to chew well and eat slowly. Do not eat and drink at the same time.
- In the fifth week you start to move on to solid food. Protein and vegetables are important. You will also learn which foods to avoid.
After a gastric bypass
- The eating plan has several stages. Your doctor decides how long each stage lasts and what you may eat. This also sets, through portion control, how you will eat in the long term.
- For the first few days you can drink only a few sips of clear liquid at a time. This lets the stomach heal without being stretched by food.
- When your doctor feels you are ready, the second stage follows, with puréed food that has the texture of a smooth pudding. Many foods need to be blended for this.
- Spices can irritate and should be avoided completely. Avoid fruit with lots of seeds, such as strawberries or kiwis, and high-fibre foods such as broccoli and cauliflower, which cannot be puréed well enough.
- You will probably eat only puréed food for a few weeks. After that, your doctor will add soft foods that are easy to chew.
- The fourth stage is the return to solid food and starts about two months after the operation. Food must be cut into small pieces. Larger amounts can cause a blockage, which may lead to pain, nausea and vomiting.
- Vitamin and mineral supplements are important. Your doctor will tell you about them.
