When you have cancer, it’s very common to feel more tired than you normally would. This can be for a number of reasons, including the cancer itself, the side effects of treatment, problems with eating or sleeping, a low blood count (anaemia), dealing with pain, and the emotional effects of cancer.

The good news is, there are things you can do to help. Here we take a look at some of the most common reasons for feeling tired when you have cancer, and provide some helpful tips and advice for helping to reduce the effects.


Why does cancer cause tiredness?

Between 70 and 80% of people with cancer suffer from tiredness. Some people are only mildly affected, while for others extreme tiredness (fatigue) can have a significant impact on their day to day life. There are a number of factors which can contribute to tiredness when you have cancer:

The cancer itself

Having cancer causes changes in your body, which can make you feel tired.

This might include changes in your hormones, for example if you have breast or prostate cancer.

Cancer can sometimes affect your bone marrow and can cause a drop in the number of red blood cells which carry oxygen around your body, and this can make you feel tired and lacking in energy.

Some cancers can cause damage to your muscles or organs, which can make you feel more tired. Meanwhile, some tumours produce proteins called cytokines, which are believed to contribute to tiredness.

Cancer treatments

Cancer treatments and their side effects can also make you feel tired. If you’ve had surgery, your body will need time and energy to heal, and if you’re experiencing pain from your treatment this can also make tiredness worse. It’s important to manage your pain effectively.

Chemotherapy and radiation therapy can be very successful in targeting cancer cells, but they can also damage healthy cells, and you may feel tired as your body works to repair itself.

Biological therapies and hormone therapies can also cause significant changes to the chemicals in your body, which can make you feel fatigued.

Treatments such as chemotherapy and radiotherapy can also cause sickness (nausea), vomiting, a lack of appetite, and problems with sleeping, all of which can contribute to tiredness.

Sometimes the medication given alongside cancer treatment can also make you feel more tired, or stop you from sleeping properly. If you think your medications are affecting you, talk to your medical team as they may be able to adjust the dosage or the time of day that you take it.


The emotional effects of cancer

Having cancer can be a worrying time. Anxiety about your cancer and the side effects of treatment, what you will do about work, and how your diagnosis will affect relationships with family and friends can cause you to feel stressed, affecting your sleep and making you feel more tired.

If you’re feeling worried or down, it can help to talk things through, whether it’s with a friend, a doctor or a counsellor. Many people also find that local support groups or online forums can be a great source of help and advice, from people who understand what you’re going through.


How can I manage cancer related tiredness?

Eat a healthy diet

Eating well and drinking plenty of fluids will help to give you some much-needed energy, and will make sure you body is getting all the nutrients it needs to repair and recover.

However, if you’re suffering from the side effects of treatment, such as nausea, mouth soreness, taste changes or a low appetite, it can be difficult to eat well.

If you can’t manage a full meal, or don’t feel up to cooking, the Live Better With community recommend snacking on healthy foods such as energy bars. Making tasty smoothies can also be an effective way of getting your daily intake of nutrients. Your medical team can also make a dietitian referral for you to get some support and advice.

From specialist cancer cookbooks to nutritional support, you can view a range of products designed to help with eating well here.

For more information and advice, see the Live Better With Guide to Cancer and Eating Well.


Stay as active as possible

When you’re having treatment for cancer, doing exercise may feel like more of a challenge. However, a little light exercise can help to maintain muscle mass, improve your sleep, boost your appetite, and also make you feel better mentally.

While you do need to give your body plenty of rest, you should also try to move around as much as you can. It’s important to take things gently, and then build up if you can, whether this means sitting up for a while rather than lying down, or going for a short walk in the fresh air with a friend.

The Live Better With community recommend following a gentle yoga programme, such as Healing Yoga for Cancer, to help keep your body mobile and relax your mind.


“Wonderful! A really good workout but offering exactly the right level of challenge. The meditation at the end is fabulous!” Live Better With community member


You should check with your doctor before beginning a new exercise programme.

For further information and advice see the Live Better With Guide to Cancer and Exercise here.


Think about what you need

It’s important to be realistic about what you can achieve. Ask yourself what’s really important to you, and don’t be afraid to say no to things. Plan ahead and set yourself small, achievable daily goals.

Remember to pace yourself, and do accept offers of help! Friends and family often want to feel that they are being useful in some way.

This might include driving you to the hospital for scans and treatments, helping with the housework, watching the children, cooking some meals, doing some shopping, or just being a good listening ear.


Get into good sleeping habits

Cancer can sometimes cause problems with sleeping. You may have problems getting to sleep at night, or you may find that you wake up during the night.

If you feel very tired in the day, it can be tempting to have a nap, but it’s important to limit your naps to no more than an hour, so they don’t affect your quality of sleep at night.

To help get a good night’s rest, it’s good to have a regular bedtime routine. Try to go to bed and get up at a similar time each day. Avoid using blue screens in the run-up to bedtime, and opt for caffeine-free drinks, such as herbal tea, in the evening.

To help relax, try taking a nice warm bath with some lavender essential oil, or listening to some soothing music. Applying a sleep balm or using an aroma diffuser can help you to drift off. The Live Better With community also recommend using a sleep mask to help block out any unwanted lights.

Many people who are undergoing cancer treatment find that practising relaxation techniques, such as breathing exercises, mindfulness or meditation can help them to relax and unwind before bed.

You can view our complete range of products to help with tiredness here.  

Tiredness is a common problem when you’re being treated for cancer. Most people find that the symptoms begin to reduce after their treatment has ended, but there are lots of things you can do to help make things easier in the meantime.

See the complete Live Better With Guide to Cancer Fatigue here.

Do you have any tips for dealing with cancer related tiredness? Or are you looking for advice or support? Why not join our community forum.