The Brain Runs on Fat: Revisiting the Preferred Fuel of Human Evolution For decades, we've been told that glucose is the primary—and preferred—fuel for the human brain. But what if that story is incomplete? Emerging research and a deeper look at our evolutionary biology suggest that ketones—not glucose—may be the brain’s true super fuel , especially in states of fasting, endurance, or low carbohydrate availability. 🦴 A Look Back: Human Evolution and Energy Our ancestors didn’t eat every 3 hours. Instead, they evolved to thrive in environments where food availability was unpredictable , and long stretches without carbohydrate were common. During those times, the body would enter nutritional ketosis , converting fat into ketone bodies like beta-hydroxybutyrate (BHB) —which are not just an alternative fuel, but in many ways a superior one . Persistence hunting (chasing prey for hours): fueled by fat, not carbs. Rapid brain growth in Homo erectus : likely supported by nu...
I am covering January a little early because we have just had the last parkrun of January so it is a good time to asses my progress against my time based goals, even if the progress goals could be better judged at the end of the month. parkrun times are all I have to go with regards to outcome goals and I have progressed my post illness PB from 17:35 to 17:21. I should also note that the 17:21 was run with the start as my 1k and then 1 mile PBs and just hanging on... yeah not great to do the first km in 16 minute flat pace according to Strava. There has also been much more consistency with my parkrun times, they are trending downwards with my times getting consistently quicker. I really feel I have a big PB in my legs and just need the competition, weather and pacing to be right. The above times set me up nicely for my target Half Marathon and mean my predicted finish time, in comparable conditions, would be sub 80.... something for me to wrap my head around as my current PB (on a...