Side Effects of Radiotherapy

Will Eating be a Problem?

Radiation treatment can cause a loss of appetite and may interfere with eating, digesting and absorbing food. Try to eat enough to help damaged tissues rebuild itself. It is not unusual to lose 0.5 – 1 kilogram per week during radiation therapy.


Eating a balanced diet is critical during your treatment. You may find it helpful to eat small meals more often and to eat a variety of different foods. A dietician will have some suggestions that will help you to maintain your weight. Coping with short-term dietary problems may be easier than you expect. Even if you’re not very hungry, it’s important to keep your protein and calorie intake high.

If it is painful to chew and swallow, your doctor may advise you to use a powdered or liquid diet supplement. Many of these products are available at pharmacies and supermarkets and come in a variety of flavours. They are tasty when used alone, combined with other foods such as pureed fruit, or when added to milkshakes.

You may lose interest in food during your treatment. Some patients do not feel like eating because of the stress of their illness and treatment. Certain medications can also change the way food tastes.

The list below suggests ways to improve your appetite and to make the most of the times when you do feel like eating.

  • Eat when you are hungry, even if it is not meal time.
  • Eat several small meals during the day rather than three big meals.
  • Ask your doctor or radiotherapist whether you can have a glass of wine or beer with your meal to increase your appetite. Keep in mind that, in certain cases, alcohol may not be allowed because it could aggravate the side effects of treatment, especially if you are receiving radiation therapy for cancer of the head, neck or upper chest area, including the oesophagus.
  • Keep simple meals in the fridge for then you become hungry.
  • If other people offer to cook for you, let them. Don’t be shy in telling them what you’d like to eat.
  • Keep healthy snacks close by for nibbling when you get the urge.
  • If you can eat only a small amount of food, you can increase the calories per serving by:
    • Adding butter or margarine.
    • Mixing canned cream soups with milk or half-and-half rather than only water.
    • Drinking eggnog, milkshakes.
    • Adding cream sauce or melted cheese to your favourite vegetables.
    • Some people find they can drink large amounts of liquids even when they do not feel like eating solid foods. If this applies to you, try to get the most from each drink by adding powdered milk, yoghurt, honey or prepared liquid supplements.

Tips on Eating

As a side effect of radiation therapy, you may find it difficult or painful to swallow. You might feel as if something is stuck in your throat. A sore or dry mouth or throat can also make it difficult to eat.

The following tips may help to make eating more comfortable:

  • Choose foods that you find palatable and are easy to eat.
  • Try changing the consistency of foods by adding fluids and using sauces and gravies to make them softer.
  • Avoid highly spiced foods and textures that are dry and rough, such as crackers.
  • Eat small meals and eat more frequently than usual.
  • Cut your food into small, bite-sized pieces.
  • Ask your doctor for special liquid medicines to reduce the pain in your throat so that you can eat and swallow more easily.
  • Liquid food supplements are easier to swallow than solids and can provide you with the calories you require to avoid unnecessary weight loss.
  • If familiar foods are no longer tasty, try new foods and use different methods of preparation.

We are here to assist you in your battle against cancer.