The ketogenic diet is known to help some people with some types of epilepsy. It has to be followed very strictly and you need to be careful about your electrolyte levels. I was on it a couple of years back for migraines, and my head did feel significantly better, but even when it was overseen by my medical team I still developed heart issues on it. (Which may be due to a minor CHD I have [mitral valve prolapse] although some people without heart defects do go on to have heart issues on Keto anyway). Now I just eat less carbs than before, whether it actually helps or not, I'm not sure.