Diet and radiotherapy

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After a diagnosis of any cancer it wise to generally improve the diet. Along with other lifestyle issues such exercise and giving up smoking, scientific evidence has showed that a healthy diet  is likely to help to:

• reduce the risks of developing further new cancers
• improves the recovery from radiotherapy and can reduce long term risks
• improve the response of radiotherapy

Otherwise during radiotherapy no specific dietary changes are needed unless specific symptoms develop. The chance of developing a side effect during radiotherapy depends on

• The area of the body treated

• The size of the radiotherapy field

• The total dose

• The dose received per day

• The length of time of the overall course

• The general condition of the patient

• Specific previous conditions e.g. ulcerative colitis

• Associated drugs such as chemotherapy

• The inherent sensitivity of the patients to radiotherapy

Apart from generally improving the diet no specific measures are required addition a healthy diet could help to improve the quality of life during radiotherapy by helping with specific symptoms such as weight gain, weight loss, nausea & poor appetite, diarrhoea, constipation, breathless, altered taste,  indigestion and dry mouth. 

Help with general early side effects

Radiotherapy may require a change of diet in some circumstances depending on what area of the body is being treated and how much dose it is receiving. Specific advice can be found on the individual radiotherapy advice sheets but the following general factors may be considered:-

Your appetite may be affected particularly if a large part of your body is being irradiated, especially if associated with some nausea. If so, try to eat several small meals rather than three large meals a day. Drink lots of fluid - try to double your normal fluid intake. If you are worried about diet ask your radiographer to refer you to a dietician. In the mean time advice on lifestyle and poor appetite may be helpful.

Your bowels may become loose later in the treatment, possibly causing diarrhoea. If this happens, cut down your intake of fruit, vegetables and fibre and try to increase your intake of eggs, milk and other dairy products. You should continue with your normal diet unless you begin to get diarrhoea.  Report any diarrhoea to the doctor or radiographer as it may be necessary for you to have tablets. Take these until the diarrhoea improves and then reduce them. Some dietary tips would also be helpful. Your bowels should have returned to normal 2-3 weeks after treatment. You can then gradually re-introduce fibre into your diet until you are back on a normal diet.