If you’ve ever felt your insides twist in knots before a big speech, you know the stomach listens carefully to the brain. In fact, the entire digestive system is closely tuned to a person’s emotions and state of mind, says William E. Whitehead, PhD, a professor of medicine and director of the Center for Functional GI and Motility Disorders at the University of North Carolina.
People with irritable bowel syndrome often suffer flare-ups during times of stress and anxiety, and even perfectly healthy people can worry their way to stomach pain, nausea, diarrhea, constipation, or other problems. Even if a doctor can’t find anything physically wrong, the misery is real.
So what do you do when you know you’re in pain, but doctors can’t pinpoint a cause?
It may surprise you to learn that the gut actually contains as many neurons (nerve cells) as the spinal cord.
In the past — back when scientists believed the mind and the body operated as separate entities — some physicians wrote off digestive distress with no sign of organic disease as being “all in the head.” But in recent years, that wall has crumbled. Doctors now see intricate links between the nervous system and the digestive system. The two realms constantly exchange streams of chemical and electrical messages, and anything that affects one is likely to affect the other. The connections between the two systems are so tight that scientists often refer to them as one entity: the brain-gut axis, an increasingly hot topic in medicine. For people suffering from persistent digestive troubles unconnected to disease, such research suggests that reducing stress, depression, and anxiety may go a long way toward calming the gut.
Listening to your gut
As strange as it sounds, our guts just might help shape our moods, says Emeran Mayer, MD, a gastroenterologist and director of the Oppenheimer Center for Neurobiology at the University of California at Los Angeles. Mayer points to the vagus nerve, essentially a large electrical cable that runs between the brain and the digestive system. “Doctors once believed the nerve’s main job was controlling acid production in the stomach,” Mayer says. “But 95 percent of the fibers go the other direction — from the gut to the brain.”
Nobody knows exactly what messages travel along this cable, but scientists have found that stimulating the nerve at different frequencies can cause either anxiety or a strong sense of well-being. Perhaps the term “gut feeling” isn’t just a figure of speech after all.
Because of the close connection between the brain and many abdominal disorders, some digestive disorders are known as “Functional Gastrointestinal Disorders,” or FGIDs.
Among these disorders is irritable bowel syndrome (IBS), a very common and perplexing disease often characterized by