Loss of appetite

Last medical review:

Loss of appetite is the loss of the desire to eat. Many people with cancer lose their appetite at some point during their cancer experience. Loss of appetite may also be called anorexia.

Loss of appetite can contribute to weight loss and malnutrition. It may not be easy, but eating as well as you can even when you don't feel like it is an important part of taking care of yourself when you have cancer.

Causes

Someone with cancer can lose their appetite for many different reasons. Loss of appetite can be caused by cancer, cancer treatments and side effects or other factors related to having cancer.

Cancer

If cancer affects the parts of your body that are related to eating or digesting food, you may not feel like eating. These types of cancer commonly include:

  • head and neck
  • colorectal
  • esophageal
  • stomach
  • pancreatic
  • liver
  • small intestine

Cancer treatments and side effects of treatment

If you are taking certain immunotherapy drugs or targeted therapy drugs, you may find that you do not feel like eating. These drugs include:

  • immunotherapy – interleukin-2 (aldesleukin, Proleukin) and interferon alfa (Intron A)
  • targeted therapy – temsirolimus (Torisel), everolimus (Afinitor) and vismodegib (Erivedge)

Cancer treatments such as surgery, chemotherapy and radiation therapy may cause side effects that affect both your appetite and your ability to eat. These effects are more common after surgery or radiation therapy for head and neck cancers or gastrointestinal (GI) tract cancers. These side effects include:

Other causes

Loss of appetite in people with cancer may also be caused by:

  • changes in metabolism caused by the cancer
  • pain
  • fatigue
  • feeling depressed or anxious
  • diarrhea
  • constipation
  • medicines – for example, opioid pain relievers
  • cancer cachexia

Symptoms

Symptoms of loss of appetite can vary depending on their cause and other factors. Everyone experiences loss of appetite in their own way. You may:

  • not feel hungry
  • eat less than usual
  • feel full after eating a small amount

Losing your appetite and your enjoyment of food can reduce your quality of life. Severe loss of appetite can lead to losing weight and to your body not getting the nutrients it needs to work well (called malnutrition).

The good news is that loss of appetite is usually temporary. Most people find that their appetite returns to normal when treatments such as radiation therapy or chemotherapy are finished.

Let your healthcare team know if loss of appetite is a problem for you.

Diagnosis

Your doctor will try to find the cause of your loss of appetite. You may be asked about the foods that you eat, and your doctor may do a physical exam or order blood chemistry tests.

Managing loss of appetite

Check with your healthcare team or a registered dietitian for suggestions on how to deal with loss of appetite. Your healthcare team can refer you to a registered dietitian.

General tips

You can try the following to help you cope with loss of appetite.

  • Eat small meals more often.
  • Eat your favourite foods when you feel well. (If you eat favourite foods when you feel sick, they may not stay your favourites.)
  • Make every bite count by eating foods that are high in calories and high in protein.
  • Make a smoothie to drink – changing the form of a food can make it more appetizing.
  • Keep snacks handy for when you feel like eating.
  • Drink a liquid meal replacement.
  • Do not drink a lot of liquid with meals. (Liquid fills you up.)
  • Eat food cold or at room temperature to reduce strong tastes and smells.
  • Try new foods that appeal to you.
  • Add seasonings to your food, such as herbs and spices.
  • Make meal times relaxed and enjoyable in whatever way is meaningful to you. Candles might make your table setting special, while listening to music might lift your mood.

For more information, learn about eating well during and after treatment.

Physical activity

Being physically active each day can improve your appetite. Try to walk for 15 minutes a day, or try other physical activities that interest you. Check with your healthcare team first to make sure exercise is safe for you.

Appetite stimulants

Your doctor may prescribe medicines to help stimulate your appetite. These may include:

  • megestrol

  • medroxyprogesterone (Provera)

  • corticosteroids

Special considerations for children

Talk to your child's healthcare team about how you can help manage your child's loss of appetite and make sure they are getting proper nutrition. You can try the following to help your child cope with loss of appetite.

  • Provide your child's favourite foods more often.

  • Let your child eat whenever they feel hungry.

  • Offer 3 small meals and several nutritious snacks every day.

  • Keep high-protein, high-energy snacks handy.

  • Make mealtimes fun – serve foods cut into interesting shapes, use colourful place settings, have a picnic, eat with a friend.

  • Do not nag or punish your child or force them to eat.

For more tips and information, check out nutrition for children with cancer.

Expert review and references

  • John Waldron, MD, MSc, FRCPC
  • American Cancer Society . Loss of Appetite . 2020 : https://www.cancer.org/.
  • Macmillan Cancer Support. Eating, Appetite, and Taste. https://www.macmillan.org.uk/.
  • American Society of Clinical Oncology (ASCO) . Cancer.net: Appetite Loss . 2020 .
  • National Cancer Institute. Appetite Loss and Cancer Treatment. National Institutes of Health; 2018: https://www.cancer.gov/.
  • Cancer Research UK. Taste Changes and Loss of Appetite . 2020: https://www.cancerresearchuk.org/.
  • Cunningham, RS. The cancer cachexia syndrome . Yarbro CH, Wujcik D, Holmes GB, eds.. Cancer Symptom Management . 4th ed. Burlington, MA: Jones and Bartlett Learning; 2014: 17:351–384.
  • Appetite problems. National Childhood Cancer Foundation & Children's Oncology Group. CureSearch. Bethesda, MD:

Medical disclaimer

The information that the Canadian Cancer Society provides does not replace your relationship with your doctor. The information is for your general use, so be sure to talk to a qualified healthcare professional before making medical decisions or if you have questions about your health.

We do our best to make sure that the information we provide is accurate and reliable but cannot guarantee that it is error-free or complete.

The Canadian Cancer Society is not responsible for the quality of the information or services provided by other organizations and mentioned on cancer.ca, nor do we endorse any service, product, treatment or therapy.


1-888-939-3333 | cancer.ca | © 2024 Canadian Cancer Society