The Dr. Oz Show episode with Dr. Joe Mercola was rerun today. He speaks about the use of ketone bodies in the brain as an alternative (to glucose) fuel:
http://www.doctoroz.com/videos/alternat ... versy-pt-2 about 4:20 into the video
Just the same explanation as the Khan Academy, JL. It appears that this information is newly accepted by the medical community. Does that mean we are on the cutting edge???
We humans CAN survive just fine on a diet without carbohydrates, starches and sugars, that convert to glucose.