It appears the brain thrives on ketones and will preferentially utilize them over glucose if they are available in the bloodstream. Now a skeptic might say the brain will use alcohol before glucose also which is true. The difference is the alcohol enters the blood brain barrier via a push mechanism. The alcohol can pass into the brain because it is there. Ketones is a pull type utilization by the brain. It will pull ketones out of the bloodstream and use them preferentially over glucose if they are available. Ketones have also been shown to not require as much oxygen in the bloodstream for optimal energy production. That is some of D'agostino's research focus. So it appears to me when you see someone who has to carry around an oxygen tank because of low oxygen blood levels, a ketogenic diet could potentially be helpful. The ATP energy production by the mitochondria is done more efficiently from an oxygen utilization standpoint burning ketones over glucose. As I recall. Might have been over glycogen.

John