Eating well can be a challenge when you have cancer. Sometimes it’s the cancer itself that prevents you from eating, digesting or absorbing food well. But usually it’s because of the side effects of cancer treatments.
Learn more about:
- Overview
- How cancer treatment can affect nutrition
- Coping with eating issues
- Fatigue
- Lowered immunity
- Loss of appetite
- Reflex (indigestion, heartburn)
- Changes in taste or smell
- Dry mouth
- Chewing and swallowing problems
- Mouth sores
- Nausea and vomiting
- Constipation
- Diarrhoea
- Dumping syndrome
- Other types of bowel irritation
- Weight loss
- Weight gain
Overview
The side effects will vary from person to person, and depend on the type of cancer, treatment and medicines you have. For some people, treatment side effects only slightly change what they can eat. For others, side effects will have a bigger impact. Most side effects that affect eating are temporary and gradually get better after treatment ends.
This section covers some of the most common impacts of cancer treatment on nutrition. It also includes practical suggestions for coping with treatment side effects and getting the nutrients you need.
Worrying about the diagnosis and treatment can also affect your appetite. If this is the case for you, talk to a family member or friend, the social worker at the hospital, your doctor or a psychologist. You can also call Cancer Council 13 11 20.
How cancer treatment can affect nutrition
Side effects vary from person to person, and depend on the type of treatment, the part of the body treated, and the length and dose of treatment.
Treatment | Possible side effects |
| surgery removes tumour or repairs part of the body | difficulty chewing and swallowing, reflux, diarrhoea, constipation, difficulty absorbing nutrients, weight loss, pain, fatigue |
| chemotherapy drugs that kill or slow the growth of cancer cells | appetite loss, nausea, vomiting, constipation, diarrhoea, mouth sores, taste changes, lowered immunity, fatigue, weight loss |
| radiation therapy the use of a controlled dose of radiation to kill or damage cancer cells; also known as radiotherapy | appetite loss, fatigue, taste changes, nausea, vomiting, diarrhoea, dry mouth, difficulty chewing or swallowing, bowel obstruction, mouth sores, reflux, weight loss, pain, fatigue |
| hormone therapy drugs that block the hormones that help some cancers grow | weight gain, appetite changes, nausea, increased cholesterol levels, constipation, mood changes |
| stem cell transplant the process of replacing stem cells destroyed by high-dose chemotherapy | lowered immunity, sore mouth and throat, nausea, vomiting, diarrhoea, fatigue, loss of appetite, weight loss |
| steroid therapy drugs used to reduce inflammation in the body | increased appetite, weight gain, increased risk of infection, stomach irritation, unstable blood sugar levels |
| targeted therapy drugs that target specific features of cancer cells to stop the cancer growing | diarrhoea, nausea, vomiting, constipation, taste changes, mouth sores, fever, increased risk of infection, weight loss |
| immunotherapy drugs that use the body’s own immune system to fight cancer | diarrhoea, bloody bowel movements, abdominal pain, bloating, weight loss or weight gain |
Coping with eating issues
Changes to how much you eat may make you feel anxious. You may worry about upsetting people who have prepared your food, or you may feel self-conscious about eating in public. It may also be hard to adjust to your changing relationship with food – for example, if you previously loved cooking and eating, but have now lost your appetite.
 | Be active every dayStudies show that exercising each day can help people feel better. It may also improve your appetite and help maintain a healthy weight. |
 | Find ways to enjoy mealtimesTake the focus off what and how much you can eat by playing music, sitting outside, lighting candles or eating with friends. This can help improve your quality of life. |
 | Try relaxation and meditationRelaxation and meditation exercises can help manage stress. You can use various recordings, videos, podcasts and apps to guide you through different exercises. Listen to our Finding Calm During Cancer podcast. |
 | Talk to someoneYou may find it useful to talk to someone who is not a family member or friend. You could speak to a dietitian, social worker, psychologist, nurse or doctor, or call Cancer Council 13 11 20. Another option is to join a cancer support group. Cancer Council can put you in touch with others by phone, in person or online. |
I went through all the symptoms you could think of – I had vomiting, diarrhoea, metallic taste in the mouth, and I lost a lot of weight. The nausea was really bad. It made my appetite go. I tried to eat, and all I could handle was dry biscuits. Chemotherapy took a toll on my body.
Marie
→ READ MORE: How to manage fatigue
Key resource
Download a PDF booklet on this topic.
More resources
Jacqueline Baker, Senior Oncology Dietitian, Chris O’Brien Lifehouse, NSW; Lauren Atkins, Advanced Accredited Practising Dietitian, OnCore Nutrition, VIC; Dr Tsien Fua, Head and Neck Radiation Oncology Specialist, Peter MacCallum Cancer Centre, VIC; Rosemerry Hodgkin, 13 11 20 Consultant, Cancer Council WA; Clare Hughes, Manager, Nutrition Unit, Cancer Council NSW; John Spurr, Consumer; Emma Vale, Senior Dietitian, GenesisCare, SA; David Wood, Consumer.
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