Keto is red hot these days, and it’s not going away anytime soon. Call it the latest dietary fad, but keep in mind a great insight Robb Wolf told Joe Rogan on his podcast: keto was “likely the default human metabolic state” over the past 2.5 million years of human evolution. Only with the extremely recent (on the evolutionary timeline) advent of civilization have we been stuffing our faces with carbs and snuffing out our magnificent ability to generate ketones as a clean-burning alternative fuel source to dietary carbohydrates. And we certainly were compelled to evolve a highly efficient mechanism to keep our high energy demand brains fueled with glucose or the glucose-like substitute of ketones at all times—for this was a matter of life or death in primal times. When our ancestors were starving, they needed to keep working hard, and concentrating hard, to find food! (This Mark's Daily Apple article was written by Mark Sisson, and is narrated by Tina Leaman)