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Ketogenic diet and brain tumours

There is currently no clinical evidence to show that a ketogenic diet can cure or control any type of tumour.

The ketogenic diet is the specialist diet that our Support team is asked about most often by our community.

If you do want to try the ketogenic diet, it’s important you do your research first and speak to your doctor or dietitian.

What is the ketogenic diet?

Ketogenic diets are very low carbohydrate diets, usually with restricted protein, but with very high levels of fat.

It‘s a very complicated diet to follow and can cause unpleasant side-effects, such as sickness, tiredness and constipation.

People following a ketogenic need to be carefully monitored by a dietitian at a specialist centre to make sure that the diet is safe, enjoyable to eat and provides all the nutrients you need.

The diet was first developed to help treat difficult to control epilepsy, usually in children.

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Our online support groups are a great place to connect with other people affected by a brain tumour and share your experience with ketogenic diets.

Ketogenic diet and brain tumours

In recent years, there’s been much interest in the role of the ketogenic diet in managing brain tumours.

This interest mainly stems from the work of American cell biologists and German medical physicists, who recommend ketogenic diets or fasting as a way of curing or controlling tumours.

Their argument is that brain tumour cells can’t use ketone bodies (the chemicals released when following a ketogenic diet) as a source of energy.

However, controlling and killing tumour cells is complex as they can easily adapt to different conditions.

As a result, most cancer specialists and cancer scientists don’t believe that a ketogenic diet can help destroy tumour cells or slow their growth.

The NICE guidelines state the patients should be advised that the evidence doesn’t support the use of alternative therapies, such as ketogenic diets, as a treatment. 

Brain tumours and brain metastases, National Institute for Health and Care Excellence, 2018

There could be a theoretical benefit to this type of diet. However, at present there’s not enough research or evidence to recommend following a ketogenic diet. 

Most of the research in this area is laboratory-based, and looks at cells in a dish or animal models (mainly specially bred mice). 

Research in humans is even more limited and studies tend to look at whether patients can follow the diet – not whether the diet makes a difference to their disease. 

These studies are often poor quality and include very limited numbers of patients. They use different types of ketogenic diets and sometimes the level of carbohydrate restriction is not even measured.

Should I follow a ketogenic diet?

Despite the lack of evidence on the efficacy of ketogenic diet treatments for malignant brain tumours, you might still choose to follow the diet.

If you wish to follow a ketogenic diet, you should only do so under the supervision and guidance of your doctor and a trained dietitian.

This is because it can affect your standard treatment and interfere with observations of your condition by your medical team. It can also cause side-effects, such as weight loss, constipation and fatigue.

Download our diet factsheet

Diet factsheet – PDF

Find out more about Diet and brain tumours in the full fact sheet.

If you have further questions, need to clarify any of the information on this page, or want to find out more about research and clinical trials, please contact our team:
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