The gut-brain connection
|Have you ever had a “gut-wrenching” experience? Do certain situations make you “feel nauseous”? Have you ever felt “butterflies” in your stomach? We use these expressions for a reason. The gastrointestinal tract is sensitive to emotion. Anger, anxiety, sadness, elation—all of these feelings (and others) can trigger symptoms in the gut.
The brain has a direct effect on the stomach. For example, the very thought of eating can release the stomach’s juices before food gets there. This connection goes both ways. A troubled intestine can send signals to the brain, just as a troubled brain can send signals to the gut. Therefore, a patient’s distressed gut can be as much the cause as the product of anxiety, stress, or depression. That’s because the brain and the gastrointestinal (GI) system are intimately connected — so intimately that they should be viewed as one system, rather than two.
This is especially true in cases where a person experiences gastrointestinal upset with no obvious physical cause. For such functional GI disorders, trying to heal a distressed gut without considering the impact of stress and emotion is like trying to improve an employee’s poor job performance without considering his manager and work environment.
Stress and the functional GI disorders
Given how closely the gut and brain interact, it becomes easier to understand why you might feel nauseated before giving a presentation, or feel intestinal pain during times of stress. That doesn’t mean, however, that functional gastrointestinal illnesses are imagined or “all in your head.” Psychology combines with physical factors to cause pain and other bowel symptoms. Psychosocial factors influence the actual physiology of the gut, as well as the modulation of symptoms. In other words, stress (or depression or other psychological factors) can affect movement and contractions of the GI tract, cause inflammation, or make you more susceptible to infection.
In addition, research suggests that some people with functional GI disorders perceive pain more acutely than other people do because their brains do not properly regulate pain signals from the GI tract. Stress can make the existing pain seem even worse.
These observations suggest that at least some patients with functional GI conditions might find relief with therapy to reduce stress or treat anxiety or depression. And sure enough, a review of 13 studies showed that patients who tried psychologically based approaches had greater improvement in their symptoms compared with patients who received conventional medical treatment.
Is stress causing your symptoms?
When evaluating whether your gastrointestinal symptoms — such as heartburn, abdominal cramps, or loose stools — are related to stress, watch for these other common symptoms of stress and report them to your clinician as well.
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