The brain’s powers are a little overrated. To keep your body going, you don’t need a functioning brain, but you do need something to provide energy. Enter the gut.
We may not give it much thought—because, literally, it happens without conscious thought—but the process of extracting energy from food is an intricate one. It involves hundreds of millions of neurons that aren’t in your brain. Those neurons are found in the outer layers of your gut, and the enteric nervous system they form is so powerful that it can work without any direct input from the brain.
The actions this nervous system performs include ensuring food passes at regulated speed, getting the right juices secreted to make digestion easier, and managing the mucus of the intestinal lining. These are crucial functions. And in the past decade, we have learned just how much of an impact the gut can have on the rest of the body and the mind.