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Constipation

Diet, fluid and physical activity

Increasing the amount of fibre you eat, drinking plenty of fluids, and being more physically active can help reduce the risk of constipation.

Increasing fibre in your diet 

The daily recommended amount of fibre for adults is 30g each day. If you eat plenty of foods high in fibre, you're less likely to become constipated. 

High fibre foods include:

  • porridge oats or high fibre breakfast cereals such as bran, plain wholewheat biscuits or shredded wholewheat

  • wholegrain, wholemeal or granary breads

  • fruit and vegetables, raw or cooked, with edible skin or peel left on

  • wholewheat pasta or brown rice

  • dried fruits, seeds or nuts

  • pulses, such as beans, peas or lentils

  • using wholegrain wheat flour for baking instead of white flour

Drinking plenty of fluids

Remember to drink plenty of fluids if you are eating a lot of fibre. Fibre draws water into the bowel, so you could get dehydrated if you don't drink enough.

Drinking plenty of fluid such as water helps to soften your poo and makes it easier to pass. Drinking between 8 and 10 glasses of fluid each day can help prevent constipation. But avoid drinking alcohol or drinks that contain caffeine, like coffee and cola, as these can contribute to dehydration.

If you find it hard to eat or drink enough

It can be difficult to eat a high fibre diet and drink enough if your cancer or its treatment is causing:

  • sickness

  • pain

  • tiredness (fatigue)

  • nutritional problems

  • breathing problems

  • a high temperature (fever) and infections

  • mouth problems

Try to eat your meals at the same time each day or eat little and often. Both may help to make your bowel motions more regular.

Your hospital or community dietitian can help you to plan a diet specifically for you.

Let your healthcare team know if you are struggling to eat or drink.

Find out more about diet problems with cancer

Physical activity

Being physically active means any movement that uses your muscles and more energy than when you’re resting. Regular physical activity helps to keep your bowel working normally.

Side effects from your cancer and its treatment can make it difficult to be physically active or exercise. You might feel that you don’t have the energy for it. But doing a little is better than none.

A short walk each day may make all the difference to keeping your bowel motions soft and regular. Exercise has also been shown to increase energy levels, so you may gradually feel better and be able to do a little more.

Read about exercise and cancer

Using a foot stool

Using a small foot stool to rest your feet on when you try to do a poo can sometimes help. It puts you into more of a squat position which assists gravity and the pressure applied by your feet can help the poo to pass more easily.

If constipation continues

Ask for help from your healthcare team if your constipation is not getting any better.

Let your doctor or nurse know as soon as you begin to have problems. The earlier you tell them, the quicker they can help to sort it out.

Find out about the causes of constipation

Last reviewed: 19 Sept 2025

Next review due: 19 Sept 2028

Causes of constipation

You might be constipated when you have cancer. There are several possible causes such as the cancer or it's treatment.

Laxatives

Laxatives can help you empty your bowels if you're constipated. If you have cancer speak to your healthcare team before taking any type of laxative.

Assessing constipation

Before you have treatment for constipation, your doctor or nurse will need to find out how bad it is and what the cause could be. Find out what they might do.

Diet problems with cancer

Cancer and its treatment can cause eating and drinking difficulties in some people. But there are people that can help and things you can do to cope better.

Types of bowel problems

The two most common problems are diarrhoea and constipation. But people with cancer might also have problems with bowel blockages, passing wind or having a colostomy or ileostomy.

Constipation main page

Constipation means having difficulty opening your bowels. Find out the causes, symptoms, and treatment of constipation.

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