Medium Chain Triglyceride (MCT) Diet and Epilepsy

The MCT diet is sometimes used to help treat epilepsy in children and reduce the frequency and severity of seizures. The diet is similar in many ways to the classical ketogenic diet, but the MCT simply refers to an oil called medium chain triglyceride that makes the diet more varied and allows the child to eat a wider variety of foods. 

What’s the difference between the two diets?  

The classical ketogenic diet utilises normal dietary fats that are a mixture of long chain triglyceride (LCT) fats and just a small amount of medium chain triglyceride (MCT) fats. 

The MCT diet is a variation of the classical version which utilises a fat supplement that consists of only MCT fats. This diet was created by Peter R. Huttenlocher MD in the 1970’s. MCT fats can produce ketones more readily than their LCT counterparts and often doesn’t need to utilise carnitine (an ammonium compound involved in metabolism in most mammals, plants, and some bacteria, used for energy) to break the fats down, unlike LCT fats. 

The MCT oil can be ingested in a number of ways:

• Taken orally, it can be purchased from the supermarket or on the internet without the need for a prescription. Coconut oil is a common example of an MCT oil. 
• Products made specifically for children who have epilepsy and are on a ketogenic diet, such as Liquigen or Betaquik. 

The MCT diet is a more flexible option that allows for a larger variety of foods, including a higher carbohydrate and protein allowance. 

How much MCT is required? 

There is no exact figure and this will need to be worked out for each child. If the amount of calories gained from MCT oils is too high it can cause tolerance issues, whereas if they are too low then enough ketones cannot be created to make it an effective treatment option. In the majority cases, the diet requires around 40% (give or take 10%) to be derived from MCT fats. In many cases, the child will start at 40% and then adapt the diet to suit. However, this will be determined by a specialised dietician who will be required to help manage the diet. 

Side effects of the MCT diet 

There are a number of potential side effects to the MCT diet, including: 

• Constipation 
• Tiredness 
• Vomiting 
• Abdominal discomfort
• Diarrhea 

These have been noted in a number of cases, however, most children may experience none of these. Just 3 in 54 observed children needed to stop the diet due to side effects such as the ones above. These side effects can often be a symptom of too much MCT and lowering the amount of MCT will often reduce or eliminate them entirely. 

Who is the diet suitable for? 

Due to the increased flexibility, the MCT diet is often thought to be more suitable for older children who have outgrown the classical ketogenic diet and require the increased variance in food sources. It’s also often used for this same reason in younger children who have become resistant to eating the more restrained classical diet. 

At the time of writing, we are unaware of any studies to suggest that the MCT diet may be effective for adults. Hopefully, this could be an interesting subject area going forward. 

How can I start my child on the MCT diet? 

Much like the classical ketogenic diet, it is not advised that you undertake the diet without the advice of a healthcare professional and an experienced specialist dietician who can help to ensure the diet is undertaken safely. As with any form of the ketogenic diet, it must be monitored closely and reviewed periodically to remain effective and ensure the wellbeing of the child. Whilst on the diet the child will need to undergo regular blood and urine tests, as well as height and weight examinations to ensure there are no issues and development is continuing as normal with the correct nutrition.