Research reveals anti-seizure mechanism of ketogenic diet therapy
Ketogenic dietary therapies have been used since the 1920s as an alternative treatment for epilepsy, particularly in children who seizures do not respond to medication.
The dietary therapies are high in fat and low in carbohydrate with a moderate use of protein. This alters the way that energy is burned in the body, using fat rather than carbohydrates as the main fuel.
Changes in the body’s fuel source means the body produces ketones - water-soluble molecules generated by the liver - and until now it was thought that the anti-seizure mechanism of the diet was the generation of these ketones.
However the new research by scientists at Royal Holloway University of London and University College London, has identified a specific fatty acid – decanoic acid – that shows potent anti-seizure mechanisms. The research is published in the scientific journal Brain.
Decanoic acid and the MCT diet
Decanoic acid is a main component of one of the ketogenic dietary therapies – the medium chain triglyceride (MCT) diet – which was developed in the 1970s as an alternative to the classic ketogenic diet. The MCT diet is based around fats derived from coconut oil. It is increasingly used for treating children but is often poorly tolerated by adults.
Decanoic acid is one of the three fatty acids in the MCT diet and it has been found to directly affect receptors in the brain and decrease seizure activity.
Professor Matthew Walker, right, from UCL and co-author of the study, told Epilepsy Society: ‘This is likely to have a large impact on the dietary treatment of epilepsy as it may be possible to use diets enriched in decanoic acid and avoid many of the unwanted side-effects of the present MCT ketogenic diet.
‘Not only that but this research has started to reveal a host of potential therapies based around fats that are much more powerful than decanoic acid, opening up the possibility of using a pill rather than a diet.’
Diet and brain function
Katrin Augustin, one of the researchers from Royal Holloway said that the research changes the way we think about nutrition.
‘We are showing for the first time that dietary fats can alter brain function,’ she said. ‘What we eat may not only affect our physical health but also our mental function, which means we may be able to regulate brain function by changes in our diet.
‘Finding a direct action for fatty acids explains why ketosis often does not correspond to seizure control, and that could be very reassuring for both patients and clinicians. It means that low ketone levels may not at all be a reason to discontinue the diet.’
Ketogenic diet research at Epilepsy Society
At Epilepsy Society a key area of research is trying to understand why some people respond to the ketogenic diet while others don’t. Director of clinical genetics Professor Sanjay Sisodiya said the latest research was an important and interesting study which leads to new understanding of the way the ketogenic diet might work to help control seizure.
‘Alongside this important study we hope that our genetic research will lead to a better understanding of why ketogenic diets work for some people but not for others,' he said. 'This will hopefully take the trial and error element out of prescribing the diet, which has to be carefully monitored. In time, we hope that we will know which treatment will work best for each individual from the point of diagnosis.’