Nervous stomach? Here's how stress affects your gut

A gastroenterologist explains how stress can lead to stomach woes.

Mercey Livingston CNET Contributor
Mercey Livingston is a health and wellness writer and certified Integrative Nutrition Health Coach. She's written about fitness and wellness for Well+Good, Women's Health, Business Insider, and Prevention.com among others. When not writing, she enjoys reading and trying out workout classes all over New York City.
Mercey Livingston
3 min read
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Stress has a sneaky way of messing with your stomach. From nervous poops to anxiety diarrhea to feeling nausea when things are uneasy, we've all experienced a nervous stomach at some point. Sometimes stress can make you lose your appetite (or do the opposite and make you crave junk). No matter what the specific experience, the tie between your gut and stress is undeniable. But is there any science behind it?

According to Dr. Marvin Singh, a gastroenterologist, the answer is yes -- stress directly affects the gut in several ways. Keep reading to find out exactly how stress can take a toll on your gut health

Stress can change your gut microbiome 

A well-balanced gut microbiome, consisting of plenty of "good" bacteria and other microorganisms, is one of the most important factors when it comes to gut health. Good gut bacteria are key to a healthy gut, and too much bad bacteria can lead to ill effects. "Stress very directly impacts gut health because it impacts the trillions of microbes that live within our digestive tracts, collectively known as the gut microbiome," says Singh. 

According to Singh, stress changes the way the gut functions, which affects the bacteria balance. Your gut microbiome can also impact your mental health through the gut-brain axis. "The composition of the gut microbiome may shift [due to chronic stress] and that could cause alterations in our mood and impact our health in other ways as well," he explains. 

Everyone experiences stress from time to time, but when it becomes chronic it's more likely to affect your gut health.

Stress may even have an effect on a person's gut microbiome before birth. A 2020 study found that pregnant women who experienced high levels of stress during pregnancy had babies with less good bacteria, leading researchers to believe that the mother's stress could be linked to the health of the baby's gut microbiome. 

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Stress can throw off the healthy balance of bacteria found in your gut.

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Stress hormones can make bad bacteria even worse 

Too much bad bacteria in the gut is, well, bad. According to Singh, stress can actually enhance bad bacteria -- meaning that the bacteria could cause even more harm to the gut than if you weren't experiencing stress.

 "Hormones and chemicals like catecholamines and serotonin are what we call quorum-sensing molecules. This means that when they are released by the gut, into the bowel, they can modify how pathogenic some bacteria might be. So basically, stress hormones and chemicals can make certain bacteria more pathogenic," explains Singh.

Stress messes with your digestive system 

Stress can wreak havoc on your stomach, often at the most inconvenient times like before a big meeting or when you're working overtime. This happens because stress changes the way your digestive tract functions. "If you are chronically stressed you might see the impacts of this alteration in the symptoms you have. Some common conditions that some might have due to altered motility include constipation, diarrhea, small intestinal bacterial overgrowth (SIBO), delayed gastric emptying, irritable bowel syndrome, and acid reflux," says Singh. 

If you experience stress-related or stress-induced stomach problems, talk to your doctor about the best treatment options. You can also consider addressing the stomach issues by working on your stress levels. Try stress management techniques that work for you like meditation, for example, or consider talking to a therapist for extra support. Even just incorporating more time to relax and have fun might make more of a difference with your stomach issues than you'd expect. 

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The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.