Cancer treatments kill cancer cells, but in the process they damage normal healthy cells and cause side effects. These side effects vary from person to person, depending on the type of treatment, the part of the body treated, and the length and dose of treatment. Most side effects are temporary and go away after treatment ends. There are ways to control and manage side effects.
The side effects of cancer treatment can affect what you can eat and how much. We discuss some of the most common nutrition impacts of cancer treatment and offer a range of practical suggestions for coping with them.
Feeling anxious about the diagnosis and treatment can also affect your appetite. Talk to a family member or friend, the social worker at the hospital, your doctor or a psychologist if you are experiencing these feelings. You can also call Cancer Council 13 11 20.
For more on this, see the treatments section for the type of cancer you have, and listen to our podcast on Appetite Loss and Nausea.
Learn more about:
- How treatment affects nutrition
- Lowered immunity
- Fatigue
- Loss of appetite
- Changes in taste or smell
- Dry mouth
- Chewing and swallowing problems
- Nausea and vomiting
- Constipation
- Diarrhoea
- Other types of bowel irritation
- Heartburn (indigestion)
How treatment affects 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 the partial or total removal of a tumour or body part |
difficulty chewing and swallowing, diarrhoea, difficulty absorbing nutrients, weight loss |
| chemotherapy the use of drugs that kill or slow the growth of cancer cells |
loss of appetite, nausea, vomiting, constipation, diarrhoea, mouth sores, difficulty swallowing, taste changes, lowered immunity, fatigue, weight loss |
| radiation therapy the use of targeted radiation to kill or injure cancer cells; also known as radiotherapy |
loss of appetite, fatigue, taste changes, nausea, vomiting, diarrhoea, dry mouth, mouth sores, difficulty swallowing, bowel obstruction, weight loss |
| steroid therapy drugs used to treat inflammation and some blood cancers |
increased appetite, weight gain, increased risk of infection, stomach irritation |
| 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 |
| hormone therapy drugs that block the hormones that help some cancers grow |
weight gain, increased cholesterol levels |
| targeted therapy drugs that attack specific particles within cells that allow cancer to grow and spread |
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 stools, abdominal pain, bloating, weight loss or weight gain |
Additional resources
Jenelle Loeliger, Head of Nutrition and Speech Pathology Department, Peter MacCallum Cancer Centre, VIC; Rebecca Blower, Public Health Advisor, Cancer Prevention, Cancer Council Queensland, QLD; Julia Davenport, Consumer; Irene Deftereos, Senior Dietitian, Western Health, VIC; Lynda Menzies, A/Senior Dietitian – Cancer Care (APD), Sunshine Coast University Hospital, QLD; Caitriona Nienaber, 13 11 20 Consultant, Cancer Council WA; Janice Savage, Consumer.
View the Cancer Council NSW editorial policy.
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