To mark World Diabetes Day, Content Developer Azmina explains how Cognitive Behavioural Therapy (CBT) can help you cope with difficult emotions when you have diabetes and cancer.

World Diabetes Day is held on 14 November every year, which was the birthday of Sir Frederick Banting who co-discovered insulin. The aim is to raise awareness of diabetes throughout the world and help people to understand the impact of the condition.

Living with two conditions
About 1 in 5 people with cancer (20%) also have diabetes.

Being diagnosed with cancer can have a huge effect on your emotions. It can be especially difficult if you are already living with another condition like diabetes. You may be frightened, stressed, angry or sad, or have all these feelings at the same time.
When you are ill or stressed, the amount of sugar in your blood increases. Some cancer treatments like steroid drugs can also directly affect your blood sugar.

If you need extra support in managing stress, you can call the:

Cognitive Behavioural Therapy (CBT)
CBT is a talking therapy based on the idea that your thoughts, feelings, physical sensations and actions are all connected.

Let us imagine that Sandra has Type 2 diabetes and takes steroids as part of her cancer treatment. She has a high blood sugar reading and reacts in this way:

Sandra responds to the high blood sugar reading by having a negative thought that she cannot cope. This makes her feel stressed, which increases her blood sugar and causes a headache and muscle tension.

As Sandra is now feeling unmotivated and unwell, she acts in ways that affect her diabetes control. Eating comfort food and not exercising will only make her blood sugar rise even higher. When she next does a blood test, it will reinforce her thought that she cannot cope. Sandra could become trapped in an unhelpful cycle

Managing your thoughts and actions
CBT could help Sandra break out of the cycle by challenging her thought pattern and actions. She could react to the high blood sugar reading in a more helpful way:

Here, Sandra replaces her negative thought about not coping with a more realistic and balanced thought. This makes her feel calmer and more in control of her diabetes. In turn, there is a positive effect on how her body feels and how she acts.

Instead of staying indoors and comfort eating, Sandra does some exercise in the fresh air. This prevents her blood sugar from getting worse and improves her mood. Sandra also makes a sensible plan to speak with her medical team. They may change the dose of her steroids or the time of day that she takes them, or suggest a different way of controlling her diabetes.

For more information
To find out more about CBT, talk to your doctor or specialist nurse. Talking therapies, including CBT, are available for free through the NHS, but it often depends on what is available in your area. Your GP may refer you to a specialist, tell you about a self-referral service, or direct you to online services. We have more information about these ways of accessing support.

For more information, you can order our free booklets Diabetes and cancer treatment and How are you feeling? The emotional effects of cancer at

You can also search the Directory of Information Materials for People Affected by Cancer. It has details of over 1,900 booklets, leaflets, books and audiovisual materials for people affected by cancer. It is regularly updated and you can use it to search for our resources and those from other organisations.


To see what else Macmillan's cancer information team has been blogging about, please visit our blog home page! You can subscribe to receive our blogs by email or RSS too.

Whatever cancer throws your way, we're right there with you. 

The Macmillan team is here to help. Our cancer support specialists can answer your questions, offer support, or simply listen if you need a chat. Call us free on 0808 808 00 00.

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