Nutrition and cancer mouth problems

Some cancer treatments cause mouth ulcers or change the amount and thickness of saliva in your mouth. These changes can make your mouth feel hot, dry or uncomfortable, and chewing or swallowing may become difficult and painful. Tooth and gum problems can occur and your lips can become dry.

Chewing and swallowing problems

People that have cancer in or around the mouth and throat may experience chewing and swallowing problems. Sometimes radiotherapy and chemotherapy to this area can also cause temporary problems. If teeth are extracted, chewing may be more difficult.

If you have pain when chewing or swallowing, tell your doctor who will be able to give advice on suitable medications.

If you have severe difficulty swallowing for a considerable period of time, a feeding tube may be considered to ensure you get adequate nutrition. Your dietitian, speech pathologist and doctor can guide you through this.

Dry or coated mouth

When your mouth is dry you are at increased risk of getting infections such as oral thrush and tooth decay which will make eating harder.

Ensure good oral hygiene. Keep your mouth clean and prevent infections with regular mouthwashes and gargles. Make sure you use an alcohol–free mouthwash to avoid further irritation to the mouth. Speak with your dentist or health care team about mouth rinses or lubricants most suitable for you during treatment.

You may wish to avoid:

  • Rough, crunchy or dry foods (chips, nuts, dry biscuits, toast). Soften foods by dipping them into milk, soups, tea and coffee.
  • Foods that sting your mouth, e.g. salty foods, spices, fruit juice, vinegar and alcohol.
  • Foods (or drinks) that are very hot or very cold. Extreme temperatures may irritate your mouth or throat.

Some helpful suggestions:

  • Choose foods that are moist or moisten foods by adding sauces, gravies, margarine, cream, custard etc.
  • Sip on fluids with all your meals and snacks.
  • Try sugar–free chewing gum or sucking on mints to stimulate the flow of saliva.
  • Sucking on ice or frequent sips of fluid (try different types) may be helpful.

Changing food textures

You may need to change the consistency of your foods by chopping, mincing or pureeing to make them easier to manage. Do not persist with a solid diet if it is taking you a lot longer to chew and swallow, or if you are experiencing coughing, choking or food sticking in your mouth or throat.

If you are having problems with your dentures, only wear them at meal times, or take them out and try softer foods that do not need to be chewed. If you are receiving radiation therapy to the head or neck area, you may need to discuss when to wear your dentures with your doctor or radiation therapist.

If you are experiencing problems swallowing normal foods and fluids, notify your doctor who may refer you to a speech pathologist for assessment.

A speech pathologist can continue to monitor your swallowing after treatment, and modify the texture of your food once the side effects that are affecting your ability to swallow and chew begin to diminish. Sometimes people may need to remain on a texture modified diet after their treatment; however this is different for everyone and will depend on the type of cancer, treatment or surgery received.

Texture modified diet

If you have been told that you need to follow a texture modified diet it can be difficult to think of foods to eat. Your dietitian can help to identify certain foods and fluids that will be easy to eat and drink.

Food textures

  • Soft diet - Soft foods can be chewed but not necessarily bitten. Foods should require minimal cutting and be easily broken up with a fork. Food should be moist or served with a sauce or gravy to increase moisture content. Food may be naturally soft or may be cooked or cut to alter its texture.
  • Minced and moist diet - Food should be soft and moist and easily form into a ball in the mouth. Small lumps can be broken up with the tongue rather than biting or chewing. Food should be easily mashed with a fork and may be presented as a thick puree with obvious lumps in it. Lumps are soft and rounded with no hard or sharp lumps.
  • Smooth pureed diet - Food is smooth, moist and lump free. It may have a grainy quality and is similar in consistency to commercial pudding. Food can be moulded, layered or piped.
This information was last reviewed in June 2013

This information has been reviewed by: Jenelle Loeliger, Head – Nutrition Department, Peter MacCallum Cancer Centre, VIC; Kate Aigner, Cancer Information Consultant, Cancer Council Helpline ACT; Ian Anderson, Consumer; Anna Boltong, PhD Candidate (Dietitian), Department of Cancer Experiences Research, Peter MacCallum Cancer Centre, VIC; Clare Hughes, Nutrition Program Manager, Cancer Council NSW; Bridget Kehoe, Public Health Coordinator (Nutrition and Physical Activity), Cancer Council QLD; Steve Pratt, Nutrition and Physical Activity Manager, Cancer Council WA; and Roswitha Stegmann, Helpline Nurse, Cancer Council WA.

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