Oncology dietitians play an integral role in helping you if you are struggling to eat and are losing weight during your treatment. We also help in providing advice on managing the side effects of your treatment and your cancer so that we can improve your nutritional wellbeing.
The videos and information on this webpage will provide you with evidence-based advice to support you during your cancer treatment.
Why is it important to eat well during cancer treatment?
Cancer treatments disrupt the way cancer cells grow and divide but they can also affect normal cells. This can cause you to feel unwell. It is therefore very important to have a healthy balanced diet appropriate to your specific needs during your treatment to keep you as well as possible. This can help you recover faster and support your body during your treatment.
Why is it important for me to keep my weight stable during my treatment?
Research has shown that people who maintain a stable weight through cancer treatment live longer and have better quality of life. It is therefore important not to lose weight during your cancer treatment even if you are overweight.
If you lose weight during treatment:
Are there any foods I need to avoid?
Your doctor, nurse or dietitian will let you know if there are any specific foods you need to avoid with your particular treatment. Most people do not need to cut out any foods from their normal diet.
Why should I eat a healthy diet?
You should follow a healthy diet if:
If you are managing well with your cancer treatment and are not having problems with eating and do not have a poor appetite you should aim to have a healthy balanced diet and keep your weight stable.
Your diet should include a selection of foods from each of the following food groups:
Foods which are high in sugar or high in saturated (animal) fats should be limited if you have a good appetite. These foods provide a large amount of energy to our diets which can result in weight gain.
Important tips for a healthy lifestyle
For further advice on healthy eating and drinking:
What should I do if I am gaining weight during my treatment?
If you start to gain weight once your treatment starts, aim to follow a healthy balanced diet.
Having cancer can change lots about your life, including your eating. You might not be cooking as much. Or you might not be as physically active as you were before. When you are having active treatment it is important not to go on a “diet”.
In addition to the healthy eating advice above you might find the following tips useful:
What should I do if I’m losing weight or struggling to eat properly?
When you are having cancer treatment you should aim to stay a stable weight. If you are losing weight you may need to make some changes to your diet. Our Patient Information Leaflets Eating when you have a small appetite and Healthy eating for weight gain will give you helpful ideas.
If your appetite is reduced it is important to make the most of each mouthful of food. There are several ways you can do this.
1. Choose foods high in energy
It is a good idea to focus on the foods that are high in energy (calories). These are often foods that you may have previously avoided e.g. cheese, full fat milk, custard, creamy soups, nuts etc.
2. Fortify your food
Adding nourishing extras to the foods that you eat can make each mouthful more wholesome. It will increase your energy and protein intake without the need for having a bigger portion.
Try to enrich food and drinks by adding extra ingredients using the table below:
|Add sugar, jam, honey to||
|Add extra fats (e.g. butter, margarine, spread, oils, mayonnaise) to||
|Add cream, creme fraiche, full cream milk to||
|Add grated cheese to||
|Add skimmed milk powder to||
|Add cream, evaporated or condensed milk, yoghurt, crème fraîche, custard or ice cream to||
Fruit and vegetables are an important source of vitamins and minerals, however they can fill you up quickly and are not rich in energy or protein. Adding butter, cheese or creamy sauces to vegetables; mayo, salad cream and full fat dressings to salad; and cream, custard or ice cream to fruit can make them more nourishing.
3. Eat regular snacks
It is common to get full more quickly when your appetite is poor. It can be helpful to have 5-6 smaller meals and snacks through the day instead of 3 larger meals.
Snacking is a great way to eat more without needing to increase your portion sizes. It can be helpful to eat whilst in front of the TV or reading a book as this will distract you and may allow you to eat more.
Examples of nourishing snacks include:
4. Drink nourishing fluids
Water is good for hydration, but it does not contain any calories or protein. Other drinks such as fruit juice, full sugar squash and milky drinks such as milk shakes, Horlicks®, hot chocolates and lattés are good for hydration and they will also be nourishing. You should aim for 8-10 cups of fluid per day. These should be a mix of water and nourishing fluids.
What can I do to manage symptoms that are affecting how I am eating?
The symptoms and side effects of cancer treatment may cause you to lose your appetite. It is important to discuss this with your doctor or specialist nurse, since there may be medications they can prescribe to help you.
If you are opening your bowels less frequently than usual and your stools are hard and difficult or painful to pass, you may be constipated. Constipation is a common side effect of cancer treatment, anti-sickness drugs and painkillers. Constipation can be very serious and cause symptoms such as tummy pain, nausea, vomiting and poor appetite.
Dietary changes may not be sufficient to relieve constipation caused by medicines. You are likely to need to take laxatives. Please consult your doctor or specialist nurse for advice.
If you are constipated follow the advice below:
Aim for at least 2 litres of fluids per day. This can include water, tea and coffee, squash, fruit juice and milky drinks.
Gentle exercise can help to stimulate the bowels. Keep as active as possible through your treatment.
You may need to increase the fibre in your diet. Good sources of fibre include: fresh fruit and vegetables, dried fruit and wholegrain products. Please be aware that a high fibre diet is not suitable for everyone. Consult your doctor or dietitian if you are unsure about the amount of fibre you should have.
Diarrhoea is a common side effect of many cancer treatments. It is unlikely due to the type of food you are eating. Please discuss this with your doctor or specialist nurse who will be able to prescribe suitable medications if appropriate.
Diarrhoea may also be a sign of infection. Check your temperature and alert your medical team if you are worried about your symptoms.
It is important to keep well hydrated when you have diarrhoea as you may be losing a lot of fluid.
Dietary changes may be useful in some cases. If your symptoms are ongoing ask your doctor or your specialist nurse to be referred to a dietitian.
Chemotherapy and some medications can cause nausea and vomiting. It is not usually related to the food you are eating. Your doctor or specialist nurse can advise you on anti-sickness medications. You may need to try several before you find the one that suits you.
You can also follow these tips to reduce nausea and increase what you are managing to eat:
Cancer and cancer treatments can cause your taste to change in the following ways:
It is important to try and eat as normally as possible even if food tastes strange. Missing meals due to altered taste can lead to weight loss.
Taste changes can come and go, so it is best to try and have what you fancy at the time. Avoid foods that don’t appeal, but try them again in a few days or weeks as your taste is likely to continue to change and you may enjoy them again.
Follow these tips to cope with taste changes:
Taste changes can also be a result of a dry mouth or oral thrush. If you notice your tongue has a thick white or yellow coating, contact your doctor or nurse specialist. They may be able to prescribe medication to help you.
A dry mouth is common during some cancer treatments. A dry mouth can allow bugs to build up. It is therefore important to frequently brush your teeth and use mouthwash. If your tongue has a thick white or yellow coating please discuss this with your doctor or specialist nurse who will be able to prescribe mouth washes or medication to help.
Tips to cope with a dry mouth:
It is important to speak to your doctor or specialist nurse if your mouth becomes sore. This can be a sign you may be developing mouth ulcers. Treating this early can stop it from getting worse.
Tips to cope with a sore mouth:
Feeling very tired is a common side effect of cancer treatment and can make shopping, cooking and eating more challenging. One of the best ways to help with fatigue is to try and do some gentle activity every day. This has been shown to help with energy levels. E.g. go for a short walk round the block, gentle house work or gardening.
Tips for coping with tiredness / fatigue:
Cancer treatment can be very stressful and frightening. You may find that this puts you off eating. Changes in your eating patterns may also cause you and those around you to worry. It can be helpful to talk to those close to you, or a counsellor about how you are feeling about your illness and treatment.
The Fountain Centre (found in St Luke’s Cancer Centre) offers advice, counselling and a range of complementary therapies, in a calming and relaxed atmosphere.
There are a number of meditation apps on Android and Apple devices which you may also find useful. Learning “Mindfulness” is currently very popular for stress relief.
It can be very difficult for family and friends to see somebody they care about struggle to eat. You may find that family members insist on giving you big portions of food because they want to help you. It can be helpful to talk through any problems you are having with eating with those around you. This will help them to understand why you are eating differently. Explain that a smaller portion of food is easier, and that you are likely to eat more if your plate is not too full.
Try not to put too much pressure on meals. Make sure you have a calm, pleasant space to eat in. Some people find being distracted with the television, music, a book or a crossword helps them to eat more without realising.
Can alternative diets be helpful?
There is a lot of attention in the media surrounding diets to “beat cancer”. This includes a lot of speculation about foods that “cure” or “feed” cancer. There is currently no scientific evidence that any of these popular diets improve cancer survival or quality of life.
Some of these ‘diets’ restrict whole food groups (e.g. dairy and gluten), when there is no need to. This puts you at risk of nutritional deficiencies and weight loss which may compromise your cancer treatment.
Alternative diets are therefore not recommended. If you are still keen to follow a particular diet, please discuss this with your doctor or nurse or ask to see a dietitian to ensure your diet is nutritionally complete.
Do I need vitamin supplements?
If you are eating a healthy balanced diet and have not lost weight, you should not need to take any extra vitamin and mineral supplements during your cancer treatment. Vitamin and mineral supplements can be helpful if you are struggling to maintain a balanced diet or have problems absorbing your food properly. These can be prescribed by your doctor if they suspect that you are lacking a particular vitamin or mineral.
Alternatively they can be bought at most pharmacies and supermarkets. A one-a-day Multivitamin and mineral tablet is recommended. Choose products that have no more than 100% of your recommended nutrient intake (RNI) for each vitamin and mineral.
It is now recommended that everyone takes a Vitamin D supplement of 10 micrograms (mcg) or 400IU per day during the winter months from October to April.
High dose vitamin and mineral supplements are not recommended as they may interact with your cancer treatment. Avoid taking supplements such as Berrocca, 500mg or 1000mg Vitamin C, 15mg or 25mg Zinc.
Herbal supplements are also not recommended during cancer treatment. They are not always tested and may cause an interaction.
If you are already taking a vitamin, mineral or herbal supplement that is not prescribed, or want to buy an over-the-counter product, always check with your doctor, nurse or dietitian that it is safe to use during your treatment.
What food safety advice do I need to follow?
Cancer treatment can make you more prone to illnesses such as food poisoning. The following advice will help prevent you becoming unwell:
Cooking and reheating
There is no longer any evidence to support the use of neutropenic diets if your white blood count is low. However it is particularly important to follow the food safety advice above to prevent food poisoning.
What do I eat at the end of my cancer treatment?
If you have finished your treatment and have no problems with eating, it is advisable to return to a healthy balanced diet. This will help you to recover and to reduce your risk of a recurrence of your cancer.
For further advice on healthy eating and drinking:
If you continue to experience difficulties eating, then continue to follow the advice you have been given by your dietitian until you are able to eat more normally. If you are worried about ongoing poor appetite, or symptoms, please discuss this with your doctor, specialist nurse or dietitian.