Why Does Stress Affect My IBS?

4 min read

Dr. Melissa Hunt


Many people with IBS notice that in times of high stress their IBS symptoms often get worse. Why does this happen? Does it mean your symptoms are “all in your head?” Absolutely not! Stress has a direct effect on the way the entire GI system works for pretty straightforward biological reasons. All vertebrate animals (including humans!) have a nervous system that controls just about everything that happens in the body. It’s divided into several different systems or sets of nerve cells that all talk to each other, including the central nervous system,which includes the brain and the spine, and the peripheral nervous system which is further divided into the autonomic and the enteric nervous systems. The autonomic nervous system is composed of the sympathetic (fight or flight)and the parasympathetic (rest and digest)systems. The enteric system controls…wait for it…the digestive system, including the stomach and the intestines. When we feel stressed, the entire nervous system gears up to help us meet whatever challenge we are faced with. The brain tells the autonomic system to increase breathing, heart rate and blood pressure, shunt blood away from the digestive system to the big muscles instead, and secrete stress hormones like adrenaline and cortisol. This automatically shuts down the parasympathetic system (which would do the opposite — like slow down the heart and reduce blood pressure). The enteric system also responds directly to these commands, either slowing down or speeding up normal digestive processes and sending signals to empty the bladder and the bowel. This often leads to tension or a tight “knot” feeling in the stomach, increased intestinal cramping and urgency, and helps explain why we often feel like we need to burp, throw up, poop and/or pee when we’re anxious.

Believe it or not, this is a great system to have in place. It helped our ancestors survive saber tooth tiger attacks, hunt down wooly mammoths, escape savannah fires, and manage all the other massive challenges they faced that required a huge output of physical energy to run or fight. Unfortunately, this system is notes useful in helping us manage the challenges and stressors of modern life. Rush hour traffic that makes you late, unpaid bills, unpleasant meetings, looming deadlines, arguments with loved ones — all of these are stressful, but none of them requires a huge output of physical effort to survive them. Sadly, our nervous system is still reacting as if every stress or we encounter is a saber tooth tiger. That means we get all juiced up (with adrenaline and other stress hormones) and then have nowhere to go with all that energy. That’s why stress can make us feel physically terrible, up to and including dramatically worsening IBS symptoms.

What’s the solution? Well, the solution is not to “avoid stress.” That’s impossible. The only way to avoid stress is by avoiding life and that’s not desirable or sustainable. You may have tried this — skipping trips or events, staying home when you don’t feel well, not socializing, passing up jobs or challenging work assignments. If you’ve tried avoidance, you know it doesn’t work. It might be tempting, and it might make you feel better in the short run, but in the long run it’s depressing and demoralizing, and it hasn’t made your IBS any better.

A much better solution is to learn to manage stress, and the impact it has on your body, more effectively. There are a number of ways to do that, all of which I’ll be detailing in future articles. But you can learn how to do one of the easiest, most effective stress management strategies here.