People with IBS have a more sensitive gastrointestinal tract, which can be irritated by stress, says Danica Barron, M.D., associate medical director at ParaDocs. The gut and the brain are thought to be connected via the brain/gut axis, which includes a link between the cognitive and emotional areas of the brain and gastrointestinal nerves. “Neuroimaging demonstrated notable structural and functional differences between IBS patients and volunteers without IBS, as well as differences in brain activity,” she says.

Stress has been found to play a significant role in bowel activity, says gastroenterologist Rabia De Latour, M.D. “The phrases ‘upset stomach’ and ‘nervous diarrhea’ probably stemmed from this link,” explains Dr. De Latour. Stress can impact the sensitivity of your intestines and their function. IBS is a disease with strong links to the mind, meaning psychological stress through multiple pathways can cause flare-ups.

Studies on animals have shown that after exposure to stressors, immune pathways mediated by the central nervous system impact the gut and can result in a flare-up of IBS. Other studies have shown that people with IBS are more likely to report changes in their stool pattern after a stressful event than people without bowel problems. The kinds of psychological stressors often reported by people with IBS include loss of a spouse or moving to a new job or a new city, says Saurabh Sethi, M.D.

Many studies have shown that mental illness is more common in people with IBS than in people with other gastrointestinal conditions, with rates ranging from 54 percent to 94 percent in treatment-seeking patients. (While an estimated 20 percent of the U.S. population have IBS, only about 30 percent of them seek treatment, says Dr. Barron.) Generalized anxiety disorder and depression are the most common psychiatric diagnoses in people with IBS.

While stress is typically a response to a specific incident, anxiety often has no identifiable root or cause. The normal function of the digestive tract is to regulate digestion and the movement of food without the need for a person to be aware of it, explains Dr. Sethi. It also shares many important connections with the brain. When you are anxious, the signals between the brain and the digestive tract may become scrambled or misinterpreted, contributing to IBS symptoms.

If you have depression, constipation may be more likely to be a symptom of your IBS than anxiety, says family physician C. Nicole Swiner, M.D.  “A lack of motivation and energy, plus decreased endorphins and serotonin, might cause decreased appetite, bloating and constipation,” Dr. Swiner says. Studies have shown a clear link between low serotonin levels in the brain and constipation as a symptom of IBS.

The relationship between IBS and stress isn’t always clear-cut. Sometimes, it’s hard to tell what came first: the mental health issue or the IBS symptoms. “Stress can worsen IBS, and IBS can worsen your response to stress, by making you feel more anxious or depressed,” says Dr. Barron. That’s why it’s crucial to treat your IBS symptoms and treat any underlying mental health issues.

Stress management can help prevent or ease IBS symptoms. Dr. Sethi recommends relaxation techniques such as deep breathing or visualization, talking to a friend, reading, listening to music, or meditation. If the symptoms of your mental illness are severe, consider psychological treatments such as cognitive-behavioral therapy, biofeedback therapy, relaxation therapy, and hypnotherapy.

It’s important for anyone who has anxiety or depression to take steps to treat the condition. For people with IBS, treating underlying mental health issues can bring about a marked improvement in their IBS symptoms. If relaxation techniques and talking therapies don’t work, you may want to consider antidepressants or antianxiety meds. Talk to your primary doctors and therapists about your treatment options.