Diet in advanced cancer

Diet problems can happen when you have advanced cancer.

What is advanced cancer?

Advanced cancer means that cancer has spread from where it first started. A cure may not be possible if you have advanced cancer. Your doctor will offer treatments that can help to control your symptoms.

Diet problems in advanced cancer

Problems with eating and drinking may get worse when your cancer gets more advanced.

Some of the common diet problems in advanced cancer are:

  • a blockage in the bowel
  • constipation
  • not enough fluid in your body (dehydration)
  • wasting syndrome (cachexia Open a glossary item)

A blockage in the bowel


Sometimes cancer in the tummy (abdominal) area can grow so that it partly or completely blocks the bowel. This can happen with ovarian, bowel or stomach cancer.

Other causes of a blocked bowel are:

  • tissues that stick to the bowel (adhesions) after previous surgery

  • thickening of tissue around the bowel that is a late side effect of radiotherapy

Your doctor may call this a bowel obstruction. The waste from the food you have digested can't get past the blockage.

This causes symptoms such as:

  • feeling bloated and full

  • loss of appetite

  • tummy (abdominal) pain which can be crampy

  • feeling sick

  • vomiting large amounts

  • constipation

  • a hard tummy (abdomen)

  • bleeding from the back passage when the blockage is in the large bowel

There are several ways of dealing with a blocked bowel.

A drip and a tube into your nose

Your doctor will admit you to the hospital if you have a completely blocked bowel. You stop eating and drinking until your bowel is working normally again. You have fluids through a drip into a vein (intravenously). This prevents you from getting dehydrated.

You will also need to have a tube into your nose and down into your stomach. This is called a nasogastric tube (NG tube). Sometimes the tube is put into your stomach through an opening on the outside of your tummy. This is called a venting gastrostomy. These tubes aim to drain fluids and stops you feeling sick. This treatment gives your bowel time to rest. 

Sometimes, with rest, swelling in the bowel can go down, and this can fix the blockage, but not always.

Surgery to unblock the bowel

It is sometimes possible to have an operation to unblock the bowel. This relieves symptoms for a longer time.

After the operation your surgeon might repair the bowel by stitching the ends back together. Sometimes it isn’t possible to do this and you may need to have a colostomy or ileostomy (stoma). A stoma is an opening from the bowel onto the abdomen. Your poo comes out of this opening into a plastic bag that sticks over it.

This is quite a big operation to go through if you have advanced cancer. It's not easy to say how much you will benefit from the operation. Speak to your doctor and family before having this operation to help you weigh up the possible risks and benefits.

A tube into your bowel to relieve the blockage

Sometimes you can have a metal tube (stent) through the blockage. 

The surgeon puts a tube with a light at the end (colonoscope) into your bowel through the back passage (rectum). This is called a colonoscopy.

The surgeon uses the colonoscope to see where the blockage is and pushes a stent through it. The stent expands and holds the bowel open so poo can pass through again. The stent stays in place to keep the bowel open.

The stent can relieve the blocked bowel and avoid the need for a big operation. This procedure might not be suitable for everyone. Talk to your specialist about it.


Instead of an operation, medicines can sometimes help to control symptoms of a blocked bowel. Unfortunately these types of treatment will usually only control your symptoms for a while.

A drug called hyoscine butylbromide (Buscopan) stops muscle spasms and reduces pain. You can also have painkillers and anti sickness medicines.

You might also have a drug called octreotide. Octreotide reduces the amount of fluid that builds up in your stomach and digestive system. It can help to control sickness.

Some people might have steroids. Steroids can help to reduce the inflammation of your bowel. They can also help to control sickness. 

Low fibre diet

Your healthcare team might recommend that you lower the amount of fibre in your diet. Only do this if your healthcare team have asked you to do it. This can sometimes help some people with a blocked bowel. By doing this, you reduce the amount of stool.


Constipation means having difficulty going for a poo (stool, bowel movement). You might:

  • not have a poo for a few days or more
  • have hard or lumpy poo
  • difficulty or having to strain more when you open your bowels

It is a common problem in advanced cancer. Some causes are:

  • not being physically active

  • a low fibre diet

  • depression

  • the side effects of some pain, anti sickness and chemotherapy drugs

  • spinal cord compression

You can feel very sick with constipation. You might feel embarrassed about it too. But do ask for help. Hospital and community nurses know how to deal with constipation. They can tell you how to prevent or relieve it.

Constipation is much easier to manage if your doctor treats it early. Adding fibre to your diet and plenty of fluids can help. But you may also need to take a laxative. Your doctor can prescribe one.

Don't take laxatives or increase your fibre intake if you have constipation with severe abdominal pain and vomiting. Your bowel may be blocked and too much fibre will make it worse. Contact your healthcare team as soon as possible.

Not enough fluid in your body (dehydration)

Not having enough fluid in your body is called dehydration.

Being dehydrated can make you feel sick, confused and tired. You might not feel like eating or drinking much when you have advanced cancer. So it can be hard to prevent dehydration.

If possible, try to drink every hour or two, even if it is only sips of your favourite fluid. You could try sucking ice cubes if you are finding it difficult to drink. 

Your doctor might give you some fluids through a drip to help. But this is not always the best solution if you are in the late stage of your cancer.

The Royal Surrey NHS Foundation Trust have a video called 'What should I eat if…I just don’t feel like drinking? Tips to support you when you are struggling to drink with cancer'.

Wasting syndrome (cachexia)

Cachexia is a problem for many people with advanced cancer. It is also called wasting syndrome or anorexia cachexia syndrome. Anorexia means loss of appetite.

Cachexia is more than only loss of appetite. It is a complex problem and difficult to control. It involves changes in the way your body uses proteins, carbohydrates, and fat. You may also burn calories faster than usual.

Cachexia in advanced cancer can be very upsetting. You might feel very weak and less able to do things. Doctors try to reverse the effects of cachexia. They use appetite stimulants, steroids and in some people, tube feeding. But improvements are only temporary. 

If you have cachexia, it might be helpful to eat whenever you can face it. Eating might not reverse the problem but can help to stabilise weight loss. This will help you feel better emotionally. It can also give you more energy and improve your quality of life.

You and your loved ones can try the following suggestions to help with cachexia:

  • Try eating in the mornings. People tend to feel more like eating in the morning than in the evenings.

  • Try to regularly eat small meals and snacks that are high in energy.

  • Don't worry too much about what you eat. If you feel like it, have it.

  • Ask the hospital dietitian for hints on how to prepare simple foods that are easy to digest.

  • Drink small amounts as often as you can if you don't feel like eating. Or try drinking high energy supplements between meals.

  • Try to still eat with your family or friends at the table. The social gathering with loved ones and the support they offer can help you to cope better.

The Royal Surrey NHS Foundation Trust have a video called 'What should I eat if...I am losing muscle and strength? Tips to support you when you have muscle loss with cancer'.

  • Improving Supportive and Palliative Care for Adults with Cancer 
    National Institute for Health and Care Excellence (NICE), March 2004

  • End of life care for adults: service delivery
    National Institute for Health and Care Excellence (NICE), October 2019

  • The Royal Marsden Hospital Manual of Clinical and Cancer Nursing Procedures (10th Edition, online)
    S Lister, J Hofland and H Grafton 
    Wiley Blackwell, 2020

  • ESMO Handbook of Nutrition and Cancer
    A Jatoi, S Kaasa and M Strijbos
    ESMO Press, 2023

  • Cancer cachexia in adult patients: ESMO clinical practice guidelines
    J Arends and others
    Annals of Oncology, 2021. Volume 6, 100092

  • The information on this page is based on literature searches and specialist checking. We used many references and there are too many to list here. If you need additional references for this information please contact with details of the particular issue you are interested in.

Last reviewed: 
27 Mar 2024
Next review due: 
26 Mar 2027

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