Many people find eating to be a problem during or after cancer treatment.

Some problems such as a lack or loss of appetite or weight loss may lead people to seek medical attention, at which point they are diagnosed with cancer. Some problems may be due to the location of the cancer in the body, causing people to feel nauseous or experience difficulty with digestion. It is important that you talk to your doctor so that your food intake can be improved before you begin your treatment.

Problems eating may also be caused by some treatments aimed at fighting cancer. These may be temporary, although some last longer. If your treatment is directed at the mouth, throat, stomach, or intestines, you will need some time before you regain a regular eating pattern. Radiotherapy treatment administered to the head and neck region may cause dryness of the mouth and difficulty swallowing. Chemotherapy may provoke nausea, vomiting, diarrhea, constipation, changes in taste, and soreness of the mouth.


Soreness and ulceration of the mucosas of the mouth and throat is called mucositis, and can be very painful. This condition can be caused by chemotherapy and radiotherapy of the the head or neck. The soreness that affects the cells that line the mouth or throat tends to be temporary, and most side effects disappear when the treatment finishes.

Useful tips for keeping a healthy mouth during treatment:

  • Drink plenty of fluids, especially water. If you notice that fresh fruit juices cause stinging, try to drink less acidic juices, such as peach, pear, blackcurrant, or rosehip syrup. Try having milk or milk-based drinks such as shakes or hot chocolate.
  • Cold foods and beverages may relieve your sore mouth. Try adding crushed ice to drinks and eating ice cream or soft milk jellies. Some find that sucking on ice can be soothing.
  • Very cold or hot drinks may irritate your mouth, so you should generally try to eat and drink things that are lukewarm or at room temperature.
  • Try drinking through a straw.
  • Avoid salty and spicy foods.
  • Stay away from rough-textured foods such as toast or raw vegetables, as these may scrape at sore areas.
  • Use sauces to soften foods.
  • Tell your doctor if you have mouth soreness; he or she may prescribe you a soothing or antiseptic spray or cream for your symptoms. You may also take painkillers before lunchtime to help with swallowing.
  • Mouthwashes can help, although many of the mouthwashes that are available at drugstores or other stores can be too strong for you. Evidence shows that salt-water mouthwashes are just as effective at relieving soreness.
  • See your dentist for support during treatment.
  • Use a soft-bristled or children's toothbrush. Refrain from using toothpicks.
  • If you wear dentures, soak them in a denture-cleansing solution overnight and leave them out for as long as you can so as to prevent them from rubbing up against your gums. If you are having radiotherapy in the jaw area, you may be advised to keep your dentures in as long as possible to help your gums retain their shape; however, if you are experiencing a great deal of soreness, it may be more comfortable to take them out.


Some people with cancer find that their taste changes, even if just temporarily. As a result, they may not be able to enjoy certain foods, everything may taste the same, or they may notice a metallic taste in their mouth.

If your taste changes, here are some tips to help make your food more enjoyable:

  • Eat foods that you like and pass on those that you don't feel like eating; after a couple of weeks go by, try these unpleasant-tasting foods again, because your taste may have changed back again.
  • Use condiments to add flavor to your food, especially herbs such as pepper, cumin, or rosemary. However, some may make your mouth sore.
  • Some people find that cold foods taste better than hot ones.
  • If your sense of taste or smell has changed, it may help to eat foods served at room temperature.
  • Serve fish, chicken, and egg dishes with sauces.
  • Use plastic utensils if you find you have a metallic taste in your mouth.


You may find that cooking requires a great effort from you or you may feel too tired to eat. These suggestions may help:

  • This is the time to start using foods that are quick and easy to prepare such as frozen, prepared, or canned foods. However, remember to completely defrost foods and properly cook all foods in order to prevent food poisoning.
  • If you know beforehand that you are going to be very tired after a treatment, try to plan out your meals. Prepare food when you feel you have more energy and freeze foods so that they will be ready when you are most tired. This is also a good time to give your family or friends a chance to help by doing some of your grocery shopping or cooking for you.
  • If you really can't bring yourself to eat, try to have energy drinks. You can make a smoothie by mixing together bananas, peaches, strawberries, or other soft fruits with fortified milk, juice, ice cream, or yogurt.


Constipation means that you are unable to have routine bowel movements. Some tips to help prevent or alleviate constipation are as follows:

  • Make sure you have plenty of fiber in your diet, including whole-wheat cereal, bread, and pasta, muesli, brown rice, and fresh fruit and vegetables.
  • Drink plenty of fluids—at least two liters a day. This is particularly important if your fiber intake increases, as such an increase without sufficient hydration may worsen your constipation.
  • Prune and fig juices are a popular home remedy for constipation.
  • Light exercise, like walking, will help.
  • If your constipation is due to the medication you are taking, you may have to take laxatives.

If you have colon cancer, ask your doctor about constipation treatment. A high-fiber diet may worsen your symptoms.


Diarrhea may be caused by chemotherapy, radiotherapy, and surgery. The treatments may affect the healthy cells that line the digestive tract, thereby causing diarrhea. Sometimes, medication or an infection may be the cause.

At times, diarrhea may be serious, making it important to contact the hospital. If you have more than 4-6 episodes of diarrhea a day, contact the hospital.

  • Make sure you have plenty of fluids (up to two liters a day) to replace the fluids you are losing; however, stay away from alcohol and coffee.
  • Eat frequent, light meals in small quantities, such as dairy products, white fish, poultry, well-cooked eggs, white bread, pasta, or rice.
  • Reduce your intake of fiber (grains, raw fruits and vegetables).
  • Avoid foods with lots of condiments and fatty foods, and eat slowly.

If your diarrhea is caused by radiotherapy or chemotherapy, it may not help to change your diet. It is important that you take any anti-diarrhea medication your doctor prescribes you.


Here are some helpful tips to help you cope with gas:

  • Eat and drink slowly. Take small bites and chew your food well.
  • Avoid gas-producing foods such as carbonated beverages.
  • A popular natural remedy is to take two teaspoons of peppermint water dissolved in hot water.
  • Light exercise, such as walking, may help.


If nausea is keeping you from eating, these tips may help:

  • Try eating dry food such as toast or cookies first thing in the morning.
  • If the smell of cooking makes you nauseous, eat cold foods or foods that only need to be heated up.
  • If possible, have someone else cook for you.
  • Stay away from fatty and fried foods.
  • Try sitting beside an open window or in a room with lots of fresh air.
  • Sit up straight and remain seated for a while after you finish eating.
  • When you feel nauseous, start by eating light foods such as soups. Gradually introduce small portions of your favorite foods until your diet becomes more balanced.
  • Foods and beverages that contain ginger may help ease your symptoms.
  • Try drinking between meals.
  • Special bracelets known as sea bands may help relieve your nausea; these use acupressure to help with dizziness.


  • If you find you can't face big meals, try to eat in small portions as often as possible.
  • Try to make your food look as attractive as possible. Place small portions of food in your plate and garnish your food with lemon, tomato, or parsley.
  • Keep snacks on hand so you can eat them whenever. These can be things such as nuts, potato chips, cheese, and yogurt.
  • Nourishing drinks can be taken throughout the day to replace small meals.
  • Eat slowly, chew food well, and relax for a bit after each meal.
  • Your appetite may vary, and you might have good days and bad days. Make the most of good days by eating well.
  • Try to eat in a room where you feel relaxed.


Some types of medication such as steroids may increase your appetite and make you want to eat more than usual. It is important to try to eat healthy foods such as fruits and vegetables instead of sweets or chips, as these may make you gain a considerable amount of weight.