text: An MCT diet, or medium chain triglyceride diet, is one form of a ketogenic diet. A ketogenic diet is one that is high in fat and extremely low in carbohydrate. It is often used to treat epilepsy, but (obviously) has other uses as well, such as in your brother's case of non-Hodgkins lymphoma.\n\nIt works by inducing ketosis and its related effects, a condition typically only present in starving individuals. Without getting too technical, in ketosis, the body stops using glucose as an energy source and starts using fat.\n\nNormally we don't want this to happen, but in the case of your brother, it could cause a reduction in chyle buildup because the body would be forced to use the chyle (which is just lymphatic fluid rich in fat and other nutrients) as an energy source.\n\nI have included below in the source information a page with guidelines for a few different ketogenic diets. The page is geared toward the ketogenic diet as a treatment for epilepsy, but the dietary guidelines themselves are the same (the ketogenic diet is the ketogenic diet, regardless of what you are using it for). Hope this helps, and best of luck to your brother.