What, when and how you eat during bowel cancer treatment can have a crucial impact on how you feel and how you recover from that treatment. 

Generally the advice is to eat a nutrient-rich and high calorie diet but there may be times when you need to change what you eat in order to adapt to  treatment side effects. Don’t leave long gaps between meals, eat smaller, more frequent meals.

Diet after bowel cancer surgery

Eating well during bowel cancer treatment is essential to a full recovery. You will probably get to to speak to a specialist dietitian after your surgery and you are likely to be advised on a low fibre diet for around six weeks after your surgery. This will allow your gut to adjust and heal, particularly important if you have had a bowel resection and/or a stoma. You can gradually reintroduce fibre and tweak your intake should you have any reaction such as discomfort, wind or diarrhoea.

If you do experience diarrhoea, tell your nurse and they can advise on a suitable treatment (such as Imodium). Don’t be tempted to reduce your liquid intake as having diarrhoea may cause dehydration. Drink the recommended amount of water and if advised to do so, add rehydration salts to your water.

Diet during radiotherapy

Radiotherapy can also cause diarrhoea so please follow the above advice if that occurs.

While you are having radiotherapy treatment, it is important to reduce or eliminate any build up of gas in the gut as this can disrupt the treatment. Some of the gas will be caused by air you swallow as you eat; to reduce this eat food slowly, chew food well and with your mouth closed. Avoid gulping fluids. If possible drink from a glass or cup rather than sucking through a straw.
Drink lukewarm rather than hot drinks, avoid chewing gum and fizzy drinks including carbonated water or beer. Wind is also caused by certain foods fermenting in your gut. Eat small amounts regularly, take peppermint oil capsules (you can buy these over-the-counter or on prescription), drink peppermint tea and gentle exercise regularly to help move any trapped wind.

Your radiotherapy plan will be based on the size and weight you are when it is drawn up, so maintaining it is important. If the side effects of your treatment are making it difficult to eat, speak to your nurse as you may need to be prescribed a protein supplement. Ideally you will base your meals on high protein /energy foods including meat, fish, eggs, cheese, full fat milk and pulses (peas and beans).

Diet during chemotherapy

Chemotherapy for bowel cancer can also give you diarrhoea and may make you feel sick too. Another common side effect of chemo is a sore mouth. All of these things may make you want to avoid food altogether but it’s really important to eat well during chemotherapy so that your body is able to deal with the powerful drugs. Eating small portions more frequently will help;  ask your medical team for help and advice, they may be able to adjust the drugs you are taking.