People who are under stress really are much more likely to have symptoms of IBS. For instance, a study of over 1700 nursing and medical students (people who we know are stressed out!) showed that their rate of IBS was double or triple the rate of IBS in the general population. Not only that, but over 40% of the females in this group of high-stress students suffered from IBS. Those that had IBS also had significantly higher anxiety, depression, stressful life events, and sleeping disorders. Interestingly, they also spent more time sitting rather than standing or walking compared to the other people in the study, and they missed more meals and ate more processed foods.
Some studies suggest that the kind of stress we’re talking about here is “big” stress—the kind related to clinical anxiety and depression, and not the ordinary kind that comes from daily, more run-of-the-mill stressors. One study suggested that it may be that for women, clinical anxiety and depression are what predict IBS symptoms, but for men, work-related stress is what brings on IBS.
Consider Your Cortisol Levels
Evidence strongly points to stress both as a significant contributor to IBS flare-ups as well as to the constancy and severity of IBS symptoms. One explanation for this is cortisol, the hormone released when a person experiences stress. When cortisol release is signaled during stress, gastrointestinal functioning changes. This change stimulates the immune system to release pro-inflammatory cells that can create low-grade inflammation in the gut.
In most of the population, cortisol helps reduce this kind of inflammation but in IBS patients, levels of pro-inflammatory cells remain high. When your body constantly reacts to stressors as if you’re being chased by a tiger, it’s likely that either your stress response is a problem or that there are a LOT of tigers around. The interaction between stress responses and the immune system seems to be what makes IBS symptoms worse.