Tips for diet problems

Speak to your healthcare team if you have a problem with diet, digestion or weight loss. They can refer you to the hospital dietitian for help. Many cancer units and hospitals now have dietitians for people with cancer. They work with your doctor to decide together on the best way to manage your diet problems.

There are ways to deal with diet problems such as taste changes, loss of appetite, diarrhoea, constipation and sickness (nausea).

Foods to try:

  • Try foods that have a strong smell, as your sense of smell is linked to taste.
  • Choose foods that have strong flavours if all your food tastes the same. Try adding garlic, lemon juice, herbs and spices, and marinades.
  • Try different textured foods like creamy or crispy foods.
  • Have warm and cold foods together, like a warm fruit pie with ice cream.
  • Tart foods have a strong taste. Consider lemons, limes, oranges and gooseberries, lemon yoghurt, lemon cheesecake, orange mouse, lemon sorbet and stewed gooseberries (avoid if you have a sore mouth).
  • You might find you prefer stronger versions of your favourite foods such as smoked ham or bacon or strongly flavoured cheese.

Preparing your food:

  • Marinate foods overnight or for a few hours (even 10 minutes will make a difference). Make a marinade with a couple of tablespoons of olive oil, and whichever herbs or spices you fancy. Add a splash of wine or some lemon juice if you like.
  • You could use a dry marinade, also called a rub. Mix up spices and herbs and rub onto uncooked meat or fish with clean hands.
  • Gravies and bottled sauces can help to add flavours to a meal.
  • Use chutney, pickle or relish to add flavours to food.
  • Italian dressings, sweet and sour sauce and sweet fruit juice will enhance flavours.

Things to avoid:

  • Avoid foods that taste strange to you, but try them again every few weeks as your taste may have gone back to normal.
  • You may want to avoid your favourite foods and drinks during chemotherapy so there is no danger of going off them for good. This is particularly useful for children.
  • Avoid hot (spicy) foods if you have a sore or infected mouth.
  • Avoid very cold or hot foods.
  • If your food tastes metallic use plastic utensils and avoid food and drinks from cans. This can help reduce the metallic taste

Other ideas:

  • Keep your mouth clean and brush your teeth well.
  • Rinse your mouth with water before you eat.

The Royal Surrey NHS Foundation Trust have a video with tips for when you have taste changes because of cancer or its treatment. 

If you find you have a loss of appetite, some of the following suggestions might help.

Preparing your food:

  • Prepare and store small servings of your favourite foods ahead of time, so there is always something to eat when you feel hungry.
  • Ask friends and relatives to help prepare meals for you. Cooking your own food can sometimes put you off eating.
  • Have a stock of convenience foods in the cupboard, such as tinned soups and puddings.

Looking after yourself:

  • Avoid getting over tired. You will find everything more difficult to cope with if you are exhausted.
  • Don't give yourself a hard time if you really don't feel like eating for a few days after treatment. It is important to drink, but you can make up for lost calories between treatments.
  • Try to focus on what you have managed to eat or drink rather than worrying about what you haven't. Keep in mind that everybody has good days and bad days.

Foods to try:

  • Add extra calories and protein to any food that you eat (using butter, milk, cream, sugar, honey and cheese).
  • Choose foods that appeal to your sense of smell and eat cold or slightly warm food if the smell of cooking puts you off eating.
  • Softer foods like scrambled eggs or pasta are sometimes easier to eat.
  • Choose nourishing fluids. Drinks that are dairy based have more energy and protein than many other drinks such as water, tea, coffee and squash.
  • Eat puddings and desserts. Foods with fat or sugar are good sources of calories.
  • Don't be afraid to try out new foods and tastes. You may be surprised at what you like.
  • With your doctor's permission, small amounts of your favourite alcoholic drink might boost your appetite.
  • Try to eat small amounts of high protein and calorie foods every 2 or 3 hours instead of 3 large meals a day. High protein foods include meat, fish, eggs, dairy foods, beans and pulses.

Other ideas:

  • Avoid filling your stomach with a large amount of liquid before eating. Drink fluids after your meal.
  • Don’t put too much food on your plate. This can put you off eating.
  • Chew food well and eat slowly.

If you are worried about losing weight, ask your doctor about high calorie drinks.

The Royal Surrey NHS Foundation Trust have a video with tips for when you've lost your appetite because of cancer or its treatment.

  • Eat smaller meals and more snacks.

  • Drink plenty of fluids to prevent dehydration. Aim for 8 to 10 cups each day. This includes tea, squash and milky drinks as well as soups, custard, jelly and ice lollies.

  • Cut down on drinking too much caffeine (particularly in coffee) and avoid alcohol. These can make your symptoms worse.

  • Avoid food or drink containing artificial sweetener such as sorbitol, mannitol or xylitol. These can make diarrhoea worse.

  • If your diet is normally very high in fibre, it might help to reduce foods that are particularly high in fibre such as beans, nuts, seeds, dried fruit, bran and raw vegetables.

  • Try not to eat too much greasy, fatty or spicy food which will be gentler on your system.

  • Ask your doctor to prescribe anti diarrhoea drugs.

It might help to keep a diary of what you eat and when you have diarrhoea. This could help you see if there are any foods that make your symptoms worse. 

If you are having cancer treatment such as chemotherapy or radiotherapy it is more likely that your diarrhoea is due to your treatment rather than anything you have eaten. You don’t necessarily need to stop eating foods that contain fibre. In this situation it’s best to try to have a healthy balanced diet if you can. Speak to your healthcare team so they can work out what is causing your diarrhoea.

The Royal Surrey NHS Foundation Trust have a video with tips for when you have diarrhoea because of cancer or its treatment.

  • Drink 10 to 12 cups of fluid each day if possible. Water, prune juice and orange juice can all help.
  • Eat foods high in fibre such as fruit, vegetables, lentils, beans and wholegrains (unless you have a blockage in your bowel).
  • Do some exercise each day, even if it is just a short walk.

Let your healthcare team know straight away if you think you are constipated.

The Royal Surrey NHS Foundation Trust have a video with tips for when you have constipation because of cancer or its treatment.

What to eat:

  • Try nibbling on dry food like crackers or biscuits first thing in the morning.
  • Try cold or slightly warm food if the smell of cooked or cooking food makes you feel sick.
  • Have several small meals and snacks each day and chew your food well.
  • Light, bland foods, such as plain toast or crackers, might be easier to eat.
  • Have a small meal a few hours before treatment (but not just before).
  • Eat fresh or tinned pineapple chunks. This helps to keep your mouth fresh and moist.
  • Have your drinks ice cold.
  • Try sips of clear, sweet liquids, like fizzy drinks or fruit juice.

Things to avoid:

  • Try not to eat or prepare food when you feel sick.
  • Avoid fried foods, fatty foods or foods with a strong smell.
  • Don’t brush your teeth just after eating.
  • Don’t fill your stomach with a large amount of liquid before eating.
  • It’s best not to do too much activity straight after eating.
  • Try and avoid mixing hot and cold foods.
  • Avoid drinking orange or grapefruit juice, which may irritate your stomach.

Ginger and peppermint:

Some people find that food and drinks with ginger and peppermint can help with nausea. You could try sucking mints, ginger biscuits, peppermint tea or ginger ale.

The Royal Surrey NHS Foundation Trust have a video with tips for nausea (sickness) because of cancer or its treatment.

  • Try to drink 8-10 cups each day.
  • Take regular sips of liquids through a straw.
  • Keep a drink by you all the time, this will remind you to drink regularly.
  • Avoid drinking while you eat. It will make you feel full quicker.
  • Suck ice cubes if you don't feel like drinking. You can flavour them with cordial or fruit juice.
  • If you are losing weight, try nourishing drinks like juices, smoothies, cordial or milky drinks.
  • Avoid drinking coffee or alcohol. These can make you more dehydrated.

The Royal Surrey NHS Foundation Trust have a video with tips for dehydration caused by cancer or its treatment.

  • Quality standard for nutrition support in adults 

    National Institute for Health and Care Excellence (NICE), November 2012

  • Diet and cancer  
    Royal Surrey NHS Foundation Trust
    Accessed October 2023

  • Eating well when you have cancer
    The Royal Marsden NHS Foundation Trust
    Accessed October 2023

  • The information on this page is based on literature searches and specialist checking. We used many references and there are too many to list here. If you need additional references for this information please contact patientinformation@cancer.org.uk with details of the particular issue you are interested in.

Last reviewed: 
02 Nov 2023
Next review due: 
02 Nov 2026

Related links