Brain working better with ketones

I'm 39 and got an unexpected good result by taking MCT oil, and after some research concluded that my brain seems to be better at utilizing ketones for energy than glucose. I got the sense that this might not be there case for everyone. Is that true? I've had glutamate excess in the brain with migraines and probably inflammations that are above normal. Is there any way to make the brain better at using glucose again. I didn't have this issue before