Types of diet problems
Cancer treatment can cause taste changes and a loss of appetite.
Food and drink can taste peculiar when you have some cancer treatments. It can also be a symptom of advanced cancer.
Cancer treatments that might cause taste changes include some:
chemotherapy drugs
targeted cancer drugs
immunotherapy drugs
other drugs such as anti sickness medicines
radiotherapy treatments
Radiotherapy to the mouth may have an affect on your sense of taste. This may be permanent or it could improve over time.
Some chemotherapy drugs cause taste changes by affecting the spit in the mouth directly. These changes can last up to a few months after the end of your treatment.
Cancer treatment can affect your sense of taste in different ways. This can include:
a constant metallic or chemical taste in your mouth
foods tasting less salty or sweet than usual
foods tasting much stronger than usual
dry mouth (xerostomia)
a change in your sense of smell
You might lose your appetite or go off certain foods because they taste different from how they usually do. These changes could cause you to lose weight.
Doctors call a loss of appetite anorexia. This is very different from the psychiatric condition anorexia nervosa.
Anorexia is common in people with cancer. Cancer itself and certain chemicals that it releases can cause a change to your appetite.
It can happen in the early stages of cancer or much later if it grows and spreads to other parts of your body.
As many as 50 in 100 people diagnosed with cancer (50%) have loss of appetite. For people with advanced cancer, up to 60 in 100 people (60%) lose their appetite to some extent.
You can also lose your appetite for a variety of reasons when you are having cancer treatment.
The side effects of the following drugs can put you off your food and drink:
chemotherapy
targeted cancer drugs
immunotherapy
painkillers
Fatigue, pain and depression can cause a lack of energy. So you might not have the motivation to eat.
Changes to your appetite can be distressing to you and your family and friends. Eating is a social and enjoyable activity, and you or they might feel upset if you don’t feel like taking part.
There are ways to deal with diet problems like taste changes, dry mouth and loss of appetite.
Last reviewed: 13 Sept 2023
Next review due: 14 Sept 2026
Medicines, soft diets, adding calories to your diet or tube feeding are some of the ways to manage diet problems.
Losing weight when you are not trying to is a common symptom in people with cancer.
The side effects of cancer and its treatments might cause problems with your eating, digestion and weight.
Having diet problems when you have cancer can affect you emotionally. But there are things you can do to help you cope.
There are lots of organisations, support groups and helpful books to help you cope with diet problems caused by cancer and its treatment.
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.

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