Medium-chain fatty acids readily cross the blood-brain barrier and can be used as fuel by the brain.

“Interestingly, we had a diet, too, that was high in medium-chain fatty acids. And although I heard the medium-chain fatty acids could readily cross the blood-brain barrier long-chain fatty acids typically don't, short-chain fatty acids sort of do. But we found very high levels of medium-chain fatty acids indicative of them and these were normal, healthy animals. So when you take medium-chain fatty acids, they are readily from the looks of our metabolomic data, just readily crossing the blood-brain barrier and capable of being used as fuel...”