Myelin is a protective layer around the brain cells and it's 100% Cholesterol, takes up 75% of your brain

Start eating RED MEAT and cooking with butter and ghee (butter with milk solids removed so it can cook at a higher temp like oil does without burning), bacon grease and beef tallow if you can get it. I save my bacon grease in a thick glass jar that won't break from hot grease. I used to use a coffee tin but those are aluminum.

Make your own Ghee:
https://rumble.com/v539nfq-simple-directions-to-make-ghee-clarified-butter-to-cook-at-a-high-temp.html