The ketogenic diet
The ketogenic diet (also called ketogenic therapy) is a specialist medical diet. It’s a treatment option for children with epilepsy whose seizures can’t be reduced or stopped with epilepsy medicine. It’s recommended in the National Institute for Health and Care Excellence (NICE) guideline for the management of epilepsy which is difficult to control.
The ketogenic diet is much higher in fats and lower in carbohydrates than a typical diet.
If you think your child might benefit from the ketogenic diet, you will need to discuss this with an epilepsy specialist.
This isn’t a treatment option for adults on the NHS yet. This is because there is currently no reliable evidence to support its use. This can make transition to adult services difficult for teenagers on the ketogenic diet.
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 a paediatrician and a paediatric dietician who are experts in the diet. This is because the balance of the diet needs to be carefully worked out for each child and because vitamins and other special supplements are needed.
It is not advisable as a treatment option for some children with some metabolic disorders or other neurological disorders.
Children can have a very individual response to the ketogenic diet. Some will have unwanted effects including weight loss, constipation or diarrhoea and high cholesterol. The doctor should be able to manage most of these.
But some children may not tolerate the side-effects. Some children have other medical conditions that mean the diet is not suitable for them at all .Some will have difficulty taking all of the fat that is needed to produce ketones and occasionally a feeding gastrostomy tube may be inserted to help these children.
Does the diet work?
Studies have shown that about half of children will have a good response to the ketogenic diet and some will become seizure free. You may notice that your child appears more alert as well. However, the ketogenic diet does not work for every child, and it is not possible to predict who it will help.
The modified ketogenic diet
There are 2 modified ketogenic diets. These are the Modified Atkins diet (MAD) and the low glycemic index treatment (LGIT) diet. The MAD involves restricting carbohydrates and encouraging fats. Protein is not restricted. On the LGIT diet carbohydrates and protein are both restricted and fats are 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 very 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.
There are a very limited number of private clinics for adults wanting to try the ketogenic diet around the country. The ketogenic diet was initially introduced for children. There is not yet enough evidence to convince the NHS to provide adult clinics.
How can I get a referral for my child?
If you would like your child to try the ketogenic diet you should ask your paediatrician to make a referral to your local ketogenic diet clinic. Most teaching hospitals in cities in the UK have a service for children. If you are an adult you should ask your GP to refer you to an adult epilepsy specialist to discuss this as an option. If there is no local NHS service, they may refer you to the clinic offered by the charity Matthew's Friends.
What does Matthew’s Friends offer?
Matthew’s Friends provide information, training, research and grants for medical ketogenic diet therapies. For detailed information on the various ketogenic diet therapies for children and adults go to their main website.
Matthew’s Friends clinics
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. To support local services, they help fund dieticians in the NHS around the country.
You can only be referred to the Matthew’s Friends clinic by a consultant. They take NHS referrals for children in geographic areas that do not offer a service. They 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 dieticians in the NHS around the country.
If you would like to see this information with references, visit the Advice and Information references section of our website. If you are unable to access the internet, please contact our Epilepsy Action Helpline freephone on 0808 800 5050.
Epilepsy Action would like to thank Dr Rachel Kneen, paediatric neurologist at Alder Hey hospital in Liverpool for reviewing this information.
Rachel has no conflict of interest.
This information has been produced under the terms of Epilepsy Action's information quality standards.
- Updated October 2016To be reviewed October 2019