Common Crohn’s Triggers

2. Smoking

Cigarettes can not only trigger flares but can also slightly raise your risk of needing surgery more frequently to treat your Crohn’s, according to a study published in March 2023 in the Journal of Gastroenterology and Hepatology Open.

“One theory is that smoking causes constriction of blood vessels, leads to inadequate oxygen flow and nutrition in the intestines, and increases biochemical mediators of inflammation,” Sartor says, “which causes injury to the area.”

And, there may be other reasons: According to a study published in May 2020 in Microorganisms, cigarette smoke is associated with an increase in symptoms, an increased risk of disease recurrence after surgery, poorer response to treatment, a higher likelihood of hospitalization, and negative long-term outcomes.

The study, which used cell cultures to examine the effects of nicotine in people with inflammatory bowel disease (IBD), found that the bacterial parasite Mycobacterium avium subspecies paratuberculosis may be responsible for worsening inflammatory symptoms in smokers.

3. Medication

Aspirin, ibuprofen, and certain antibiotics are a few of the medications that can trigger Crohn’s flares. (Antibiotics change the balance of bacteria in the intestines, which can activate diarrhea, even in people who don’t have Crohn’s, says Sartor.)

4. Diet

Foods can change the bacterial profile in your gut, triggering symptoms. No one food will cause flare-ups in everyone, so you should track your diet to determine the culprits.

In general, though, you may want to avoid foods that can increase gas and diarrhea, such as greasy and fried foods, beans, cabbage, and carbonated drinks. It’s also a good idea to stay away from raw vegetables, watermelon seeds, peanuts, and popcorn if you are among those with Crohn’s disease who have a narrowing of the intestines, which increases the risk of intestinal obstruction, says Sartor.

Unfortunately, there’s no definitive evidence of how diet affects IBD, and doctors are not yet able to make recommendations on what you definitely should eat or avoid. In most cases, people with Crohn’s and other conditions, such as ulcerative colitis (UC), are advised to eat a healthy, well-balanced diet and steer clear of processed food.

The research notes that diets high in fruits and vegetables and low in animal fat and sugar may decrease the risk for IBD. According to the Crohn’s & Colitis Foundation, a Mediterranean diet has also been shown to help control Crohn’s symptoms and bring about remission.

5. Infection

Infections can also precipitate flare-ups, according to Sartor. “We know that gut infections can kick off symptoms in patients whose symptoms had been [in remission],” he says.

There’s also some evidence that bacterial and viral infections can set off Crohn’s in people who have never had any symptoms. For example, he says, you may go on vacation and contract an infection — think Montezuma’s revenge — from exposure to E. coli. Although other travelers may get better without any residual problems, you may lack a mechanism to turn off the inflammation if you’re genetically susceptible to Crohn’s, Sartor explains.

Another possible Crohn’s trigger is a Clostridioides difficile (C. diff) infection. According to the American College of Gastroenterology, people with IBD are more likely to contract a C. diff infection than those without IBD. What’s more, the infection “can actually precipitate IBD flares,” says Kelly Cushing-Damm, MD, a clinical instructor at the medical school and gastroenterologist who specializes in IBD at the University of Michigan in Ann Arbor. “That’s probably the most significant infection that we see for flares.”

Taking antibiotics may increase the risk of C. diff. “If someone with Crohn’s develops worsening symptoms after a recent course of antibiotics, that would lead us to think about this particular infection,” says Dr. Cushing-Damm.

Cytomegalovirus (CMV) is another virus that may trigger Crohn’s, says Cushing-Damm. “CMV tends to be a higher risk for patients who have been immunosuppressed for a period of time, such as patients on steroids.”

6. Seasonal Changes

You may have flare-ups at different times of the year. “One theory is that it might have something to do with an allergy to pollen or exposure to respiratory infections,” says Sartor.

7. Not Taking Your Medication

If you’re experiencing side effects or other problems that are interfering with your ability to take your medications as directed, you could experience a flare as a result. In that case, it’s important to work with your doctors to find a solution, says Cushing-Damm.

Crohn’s Symptoms: Identifying Your Triggers

Before you can avoid triggers, you have to identify them. Because triggers can vary from person to person, the best strategy is to keep track of the circumstances surrounding your flare-ups. Answer these questions a doctor would ask:

• Are you taking ibuprofen, aspirin, or a similar medication?
• Were you recently on antibiotics?
• Did you recently have an infection?
• Have you traveled recently?
• Do you smoke?
• In the weeks before your flare-up, did you feel stressed?
• Have you experienced anything else unusual?

Another useful way to identify triggers is to keep a food journal. It’s probably not necessary to write down every bite, Sartor says, but it makes sense to get into the habit of listing the foods and beverages you consume each day — particularly, ones that commonly trigger Crohn’s symptoms.

By keeping track of your daily routine as well, you can be your own detective and uncover any common threads between your flare-ups.

Crohn’s Symptoms: Avoiding Triggers and Calming Their Effects

Once you’ve identified your Crohn’s triggers, the next step is to avoid them.

• If you suspect stress is one of your triggers, do what you can to eliminate (or at least reduce) your stress levels. Try yoga, meditation, breathing exercises, or listening to music — whatever helps you relax. You may need to talk with your doctor about starting talk therapy or medication that may help lower your stress levels.
• If you smoke, find a way to stop.
• Avoid aspirin and ibuprofen and switch to acetaminophen, which should not trigger Crohn’s flare-ups.
• Avoid foods that are more likely to cause gas or increase the risk of intestinal obstruction.

By identifying and then avoiding all possible triggers, you can reduce the number of Crohn’s flare-ups you experience.