Weight loss injections and cancer
Weight management and cancer
There is a lot in the news about weight loss injections such as Ozempic, Wegovy and Mounjaro. These are sometimes called GLP-1 drugs (glucagon-like peptide-1 receptor agonists). These drugs work by making people feel fuller for longer and reducing their appetite.
Many people across the UK are overweight and are looking for ways to help manage this. They may worry that extra weight can harm their health and increase the risk of conditions like diabetes, heart problems, stroke and cancer.
People living with cancer sometimes want to manage their weight and make changes because they:
- are preparing for or having treatment and want to be healthier
- have finished cancer treatment and want to make changes to improve their health
Losing weight can be challenging at any time but with the extra stress of a cancer diagnosis it can be even more so. We hope this blog helps answer some of the questions you might have about weight loss injections and cancer.
Should I be worried about cancer risk if I am overweight?
Amongst the general risks for developing cancer are some lifestyle factors such as your diet, your weight and how active you are. About 4 in 10 cancers (40%) could be prevented. Living a healthier lifestyle can help reduce your risk. And while you can’t reduce your risk of cancer completely, managing your weight can have a range of health benefits. For example, it can reduce your risk of conditions like diabetes, stroke and heart disease.
What can I do about my weight if I get a cancer diagnosis?
Your healthcare team can suggest things that are realistic and suitable for you. They can give you help and support. This is called prehabilitation and aims to get you as fit and healthy as possible, before, during and after treatment.
What if I’m unhappy with my weight after cancer treatment?
Cancer and treatments can cause changes to your body. These can affect how you think and feel about your body.
Changes to your body may be temporary or permanent. They include changes that other people can see, such as hair loss or weight gain. They also include changes that are not obviously visible to others. People of any age or gender and with any type of cancer can have body image concerns.
You will need time to recover from treatment and to adapt to body changes. Even if your body looks or feels different, you can feel proud about it getting you through treatment.
Eating healthily, getting enough sleep and being more physically active are ways of taking care of your body. This may help you feel more in control and improve your body image.
Can weight loss injections reduce my risk of cancer?
Decisions to prescribe these weight loss drugs are based on factors like the person’s body mass index (BMI) and whether they have other weight-related issues. These drugs should be used alongside lifestyle changes such as a healthy diet and increased physical activity.
It is important not to take these drugs without medical advice as they have side effects and risks.
Some people have been buying weight loss injections online from unregulated sources. And there are reports of people experiencing severe side effects from fake medicines. This is another reason to make sure you take medical advice if you are considering using these drugs.
Can weight loss injections cause cancer?
Studies with animals receiving these injections have shown an increased risk of thyroid tumours. This has not been shown in clinical trials with humans but there is ongoing research into this.Can I use weight loss injections during or after cancer treatment?
There is currently not a lot of evidence around how weight loss injections such as Ozempic, Mounjaro and Liraglutide might affect anti-cancer treatments. But we do know that these drugs may affect how other drugs are absorbed by your body. This may include some anti-cancer drugs. More research is needed.
You should talk to your cancer doctor, nurse or pharmacist before taking any drugs that are not prescribed for you.
What are the side effects of weight loss drugs?
The main side effects of weight loss drugs include:
- nausea and vomiting
- indigestion
- diarrhoea or constipation
- stomach pain
- fatigue.
There is also an increased risk of becoming pregnant while taking these injections. Reports of unplanned pregnancies while taking these drugs are thought to be because the effectiveness of the oral contraceptive pill is affected. This can happen when you first start the weight loss treatment or if you increase your dose. It is important not to get pregnant during some cancer treatments as cancer drugs may harm a developing baby.
How can I lose weight in a healthy way?
It’s not always easy to make changes to your lifestyle. This can be more difficult when you’re also coping with cancer and its treatment. Some people find it helps to get support from others in a similar situation through support groups or online forums. The Macmillan Online Community is a free online place for people living with to chat about the issues affecting them
You may want to make gradual changes to your diet when you feel ready, and at a budget you can afford. It can take time to find healthy foods that you like, or a diet that works for you.
Before making changes to your diet, it can help to talk to a dietitian, your GP or a specialist nurse. This may also be useful if you have special dietary requirements or medical needs. A dietitian can advise you and help you make changes. They can also support you with any other dietary problems you might have during or after cancer treatment.
It can be helpful to know about the different types of food groups and what energy the body gets from them. Try to get a balance of different types of food to make sure you are getting the nutrients your body needs. We have more information about the different food types.
Eating well and keeping to a healthy weight will help you feel stronger and increase your energy levels. It can also keep your immune system healthy and improve your sense of well-being. This can help you cope better with cancer treatment.
Read more
-
Blogs 22 May 2025It has been reported in the news recently that extra cancer screenings could detect early cases of breast cancer in dense breasts. In this blog, we try and answer some of the questions people might...
-
Blogs 22 Apr 2025The UK Government has recently published a Green Paper that outlines potential changes to the benefits system. In this blog, we explain how it might impact people living with cancer.
-
Blogs 29 Apr 2025In this blog, we discuss ways people with cancer can get support to meet their spiritual needs and how to have conversations about your spirituality, religion and faith with your health care team.
How we can help