Eating and drinking during Radiotherapy to the pelvis

In order to improve the accuracy of your treatment, it is better if your bowels are opened on a regular basis. If you have an irregular bowel habit it is important to let your radiotherapy team know and they can advise or give you medication to help with this.

Reducing wind

Before your treatment planning takes place, it is useful to reduce the amount of wind or gas in the bowel. Production of wind (or flatulence) is a natural part of the digestion process and most of it comes from the air we swallow when eating and drinking, and some come from the types of food being eaten. Everyone has wind, which can lead to an excess being built up causing discomfort and affecting the accuracy of the radiotherapy by pushing organs to a different position.

The advice in this booklet will help you to avoid a build-up of gas, and help to relieve any symptoms of trapped wind and stomach ache during treatment.

The amount of wind we produce depends on the food eaten together with our own individual digestive process. A food and symptom diary may help you to identify which foods make your symptoms worse.

Food and drinks that can cause wind are:

• Brussel sprouts, cabbage, cauliflower, broccoli, onion, radishes, spinach, sweetcorn, peas, lentils, beans and pulses
• Spicy foods (if you are not used to them)
• Excessive amounts of fruit or dried fruit
• Fizzy or carbonated drinks, beer/lager
• Large amounts of artificial sweeteners and sugar-free sweets
• Chewing gum
• Caffeine

Identify potential causes of wind in your diet and try to reduce them during your radiotherapy treatment.

The following suggestions will help to maintain a healthy bowel habit:

• Aim to have a regular meal pattern and do not skip meals or leave long gaps between eating.
• Take time to eat your meals, eat foods slowly and chew foods well.

Minimise swallowing air when eating:

• • Do not talk while you are eating
  • Drink slowly – sip drinks rather than gulping, especially when taking tablets
  • Avoid using straws or drinking directly from a bottle
  • Avoid carbonated drinks e.g. soda water, sparkling water, cola, lemonade etc.
  • Avoid chewing gum or smoking
• Eat in a relaxed atmosphere.
• Take time to relax.
• A small amount of light physical activity each day will encourage bowel movement, for example walking or stretching.
• Oats, whole or ground linseed (up to 1 tablespoon) will help to relieve wind.
• Empty your bowels while sitting correctly – it is easier when in a squatting position. Put your feet on a footstool to raise your knees higher than your hips and lean forward.
• Peppermint tea or peppermint oil may help relieve wind or bloating.

Make one change at a time so that you can identify what has helped and made a difference.

Fluids and their importance

Water is essential for life. We need water to get rid of waste products from the body, keep our skin healthy and replace water lost through breathing and sweating.

If you do not drink enough fluid each day you can become dehydrated. This can cause:

• Tiredness
• Nausea
• Light – headedness or dizziness
• Irritability
• Poor concentration
• Constipation
• Wind and bloating associated with constipation
• Headaches
• Dry skin and mouth
• Dark coloured urine and a strong smell

How much fluid do I need to drink?

During your treatment, you should aim to drink 2 litres of fluid each day, dependent on weight, unless previous medical advice given to you states otherwise. This is equal to 3 ½ pints or 8 tumbler glasses. The radiographers or doctor may advise you to drink more as your treatment progresses; they will discuss this with you if needed.

What should I drink?

The best types of fluid to drink during your treatment are water, milk, still squash, and herbal, or fruit tea. If you drink tea or coffee, be aware of the amount of caffeine you are consuming and it is recommended you switch to decaffeinated versions. Caffeine and alcohol are dehydrating and can irritate the bowel and bladder which is why we suggest you avoid drinking these. If you are reducing your caffeine intake do this slowly, day by day, otherwise you may experience some headaches.

Fluid intake is particularly important during your radiotherapy treatment as it helps to prevent constipation, wind, bloating, and keeps your bowels opening regularly.

Some fruit juices might interfere with the way some medicines work. Discuss this with your GP or pharmacist before starting to drink cranberry or grapefruit juice.

What is fibre?

Fibre is the part of food the body cannot break down. As fibre passes through the bowels it absorbs water like a sponge, making the contents of your bowels soft and bulky. This helps the muscles in the walls of your bowel assist the food to pass through your gut more easily.

When your diet is low in fibre, the gut struggles to work well and can lead to constipation. Fibre is an important part of a healthy balanced diet which helps with the normal functioning of the bowel and has many other health benefits.

Fibre comes from 3 main sources; fruit, vegetables and wholegrain cereals. There are 2 types of fibre and our bodies need both:

Soluble fibre – this type of fibre can be digested by the body and is turned into a gel by the natural bacteria in the bowels, making your stool softer and bulky. Foods containing soluble fibre include oats, lentils, pulses (peas, beans and lentils), fruits and vegetables.

Insoluble fibre – this type of fibre cannot be digested and is less easily broken down. It passes through the body mostly unchanged but does absorb water. This increases the size of your stool and helps improve bowel movement. Foods with insoluble fibre include fruit and vegetables with skins, pips, nuts, seeds and wholegrain foods.

Fruit and vegetables contain a mixture of soluble and insoluble fibre.

Should I eat fibre during my treatment?

It is important to eat foods containing fibre as part of your diet during your radiotherapy treatment in order to keep your bowels opening regularly. Fibre has other health benefits including reducing the risk of heart disease, keeping the inside of your bowel healthy and preventing constipation.

If you are altering your dietary fibre intake, do this gradually to allow your bowel time to adjust.

What if I develop diarrhoea?

Radiotherapy to the pelvis can irritate the bowel and cause diarrhoea. You may experience wind and/or stomach cramps.

These symptoms may happen from a few days to a week or two after starting treatment and can continue for some weeks after the radiotherapy treatment has been completed. This depends on the area of your pelvis being treated.

If you experience diarrhoea during your treatment, let your radiographers or doctor know as they can recommend medication to help with this. You will need to drink more fluids to replace those lost. Your radiographers or doctor will advise you further.

If you are taking laxatives for constipation, you should let the treatment team know. You may be advised to stop these.

There is no evidence to suggest that reducing the amount of fibre in your diet improves diarrhoea caused by radiotherapy.

There is a study showing a high fibre diet is beneficial for people with radiation-induced diarrhoea*.

Continue to eat your normal diet during treatment. Certain foods and drinks may worsen the diarrhoea. Small, simple dietary changes may temporarily be required that are tailored to your individual needs. It is important to avoid any unnecessary restrictions.

This information provides general guidance and ideas. If you require more information or guidance, please ask your radiotherapy team.