If you’ve ever had butterflies in your stomach as you waited to make a speech or if you’ve sprinted to the bathroom before a job interview, then you understand how powerful—and at times uncomfortable—the brain-gut connection can be. “About 70 percent of us react to challenges by having some kind of GI symptom,” says Brenda B. Toner, PhD, professor of psychiatry and head of the Women’s Mental Health Program at the University of Toronto and cohead of Social Equity and Health Research at Toronto’s Centre for Addiction & Mental Health.
But lately scientists have discovered that the mind-gut interplay can also work the other way: to calm your stomach rather than upset it. You already know that the central nervous system of your body consists of your brain and spinal cord. What may be news is that you also have the enteric nervous system, which is located in your gut and controls digestion.
This is often referred to as the “little brain” because it has more nerve endings than the spinal cord and manufactures some 90 percent of the body’s serotonin. It trades messages with the “big brain” in the skull.
Although scientists are just beginning to study exactly how the two brains interact, it appears that signals between them can speed up or slow down the passage of food through the digestive system, prompt an amplified pain response to normal bowel contractions or trigger the release of stress hormones.
Such reactions are common, if unpleasant. But for some people, digestive snafus become a chronic condition: An estimated 20 percent of American adults—one and a half times more women than men—suffer from the painful symptoms of irritable bowel syndrome (IBS), including recurring bouts of diarrhea, constipation, gas and bloating. And while stress is not the primary cause of the syndrome—some sufferers may be genetically predisposed to hypersensitivity in the gut, while others develop IBS after a bacterial stomach infection—anxiety or other intense feelings can worsen symptoms.
Since there is no pharmaceutical or dietary fix that works consistently, especially for people with more severe IBS, there is growing interest in working to exploit the brain-gut connection through psychotherapy. Cognitive behavioral therapy (CBT), in particular, has shown good results, and its techniques may also benefit those who suffer from milder digestive turmoil.
CHANGE YOUR THINKING, REDUCE YOUR SYMPTOMS
Cognitive behavioral therapy holds that what we think about an event is even more important than the event itself in determining our physical and emotional reactions. CBT practitioners typically treat patients suffering from psychological problems such as depression and anxiety, but researchers have recently explored employing CBT, in conjunction with other medical therapies, to help treat physical disorders, such as diabetes.
Toner, coauthor of the book Cognitive-Behavioral Treatment of Irritable Bowel Syndrome, explains how the mind-body connection can ease symptoms: “If you anticipate having diarrhea or an ‘accident,’ you tend to become anxious. And when you’re anxious, pain is amplified; you swallow more air than usual, which causes the belly to be distended; and you send messages to the bowels that make you more likely to have the diarrhea you’re so worried about. By learning to restructure your thought patterns through CBT to quell the anxiety, you tone down the body’s stress response as well.” Women, who are expected to be ladylike and prevent noises issuing from their digestive systems, are especially prone to becoming anxious about their symptoms.