Ketogenic diet for epilepsy

The ketogenic diet (also called ketogenic therapy) is a specialist medical diet which is much higher in fats and lower in carbohydrates than a typical diet.

This information describes what the ketogenic diet is, why medical supervision is needed for it, who it is for and how it is accessed.

Selection of foods including fish and vegetables

Who is the ketogenic diet for?

The ketogenic diet is a treatment option for some people with epilepsy whose seizures are difficult to control. The National Institute for Health and Care Excellence (NICE) guidance says that the diet can be considered for:

  • People whose seizures can’t be stopped with epilepsy medicine, and other treatments have not worked or are not appropriate
  • People with certain epilepsy syndromes

If you think you or your child might benefit from the ketogenic diet, you will need to discuss this with an epilepsy specialist.

How does the ketogenic diet work?

We don’t completely understand how the ketogenic diet works but there is some evidence that the brain needs energy from glucose (a sugar) to create a seizure.  The ketogenic diet makes the body think that it’s in a state of starvation or fast.

In this situation, our bodies use fat instead of carbohydrates (complex sugars or starches) as the main energy source. So the ketogenic diet gives a much higher amount of fat than is found in a normal diet, enough protein for growth and a very small amount of carbohydrate. This makes the body’s ketones. The brain uses these for energy instead of glucose. It also reduces the amount of glucose available for the brain.

Why do you need medical supervision to go on this diet?

The ketogenic diet is not a ‘natural’ treatment for epilepsy as it’s not a natural diet. It should only be managed by a team of epilepsy specialists who are experts in the diet. This is because the balance of the diet needs to be carefully worked out for each person and because vitamins and other special supplements are needed.

It is not advisable as a treatment option for some people with some metabolic disorders or other neurological disorders.

People can have a very individual response to the ketogenic diet. Some people will have unwanted effects including weight loss, constipation or diarrhoea and high cholesterol. The doctor should be able to manage most of these, but you may find the side-effects are too difficult to cope with.

If you have certain  other medical conditions, it may mean that the diet is not suitable for you.

Does the diet work?

So far, there has been more research into the use of ketogenic diets for children than for adults. Some studies have shown that about half of children will have a good response to the ketogenic diet and some will become seizure free.

However, the ketogenic diet does not work for everyone, and it is not possible to predict who it will help. More high quality research is needed to find out how well these diets work in treating epilepsy.

The modified ketogenic diet

There are 2 modified ketogenic diets. These are the modified Atkins diet (MAD) and the low glycaemic index treatment (LGIT) diet.

The MAD is low in carbohydrates but high in fat. Protein is not restricted. On the LGIT diet carbohydrates and protein are both restricted and fat is positively encouraged.

These 2 modified diets are less strict than the ketogenic diet and weighing of food is not needed. The MAD is increasingly being chosen for children.

Can adults use these diets?

There is limited evidence for how effective or tolerable the ketogenic diet is for adults. But because, as an adult, you can choose what you eat, you may well find the modified ketogenic diets are easier to tolerate.

It is still important to have some medical guidance for these diets, especially if you have any other health conditions or take other medicines.

What does Matthew’s Friends offer?

The Matthew’s Friends charity provides a huge amount of information, training, research and support for medical ketogenic dietary therapies. This is for medical professionals, families and patients. It includes their website, YouTube tutorial and cooking channels and social media.

They have online ketogenic support forums for families on Facebook and a professional forum on their website. They also provide online training tutorials.  For detailed information on the various ketogenic dietary therapies for children and adults go to their main website.

Matthew’s Friends clinical service

Matthew’s Friends also have a clinic in Surrey based with the epilepsy organisation Young Epilepsy. This offers support on medically supervised diets for children and adults, where there is no local service available. To support local services, they help fund dietitians in the NHS around the country.

You can only be referred to the Matthew’s Friends clinic by a doctor.  Matthew’s Friends also take private patients and referrals from overseas. You would need to make a funding application – talk to your family doctor about how to make an application.

What does Daisy Garland offer?

Daisy Garland offers information about childhood epilepsy, the ketogenic diet and the Modified Atkins diet. To support local services, they also help fund dietitians in the NHS around the country.

Published: July 2022
Last modified: July 2023
To be reviewed: October 2022
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