The gut-brain connection is an interesting one because it travels in two directions—from the brain to the gut and from the gut to the brain. For the longest time this connection was thought to only travel in one direction, from the brain to the gut, like when strong emotions trigger an upset stomach. But researchers now know that what happens in your gut has an effect on your brain.

One recent study at the Stanford University School of Medicine tried to elucidate this connection. According to one of the researchers, “Gastric irritation during the first few days of life may reset the brain into a permanently depressed state.” Genetic susceptibility also plays a role, of course, since not all stomach upsets will lead to depression, but this connection is interesting.

The gut is connected directly to the brain by the vagus nerve, and even has a nervous system of its own—the enteric nervous system. This connection between the gut and the brain allows for close communication. Many studies are finding that the gut has a major effect on the brain. I have blogged about it before. More than once.

The researchers used an animal model of functional dyspepsia, also known as indigestion, to determine that stomach irritation early in life can lead to depressed and anxious behaviors that last much longer than the indigestion itself. Their findings will lead to more studies to investigate how this gut brain connection works, and if new ways can be found to treat depression and anxiety in humans, based on the gut-brain link.