Should You Go Gluten Free if You Have Ulcerative Colitis?

Heather Hanks battled severe bloating, constipation, gas, incontinence, and pain from ulcerative colitis for years, often ending up in the emergency room for particularly bad flare-ups. But, when she stopped eating gluten (a protein found in grains such as wheat, barley, and rye), everything changed.

“When I went gluten free and made other dietary changes, I regained control over my digestive system,” explains Hanks, a holistic nutritionist who specializes in the management of chronic disease. “I’m regular, healthy, and no longer have to be near a bathroom at all times.”

Hanks isn’t alone. Many people with inflammatory bowel disease (IBD) — ulcerative colitis or Crohn’s disease — report an improvement in their symptoms after cutting out gluten. In a review published in February 2022 in the journal Nutrients, researchers noted that some studies have found that eating a gluten-free diet may improve symptoms of IBD. In one large-scale study, the review notes, nearly two-thirds of people with IBD who tried a gluten-free diet reported improvement in their gastrointestinal (GI) symptoms.

That said, the study authors also note that there isn’t enough strong evidence to recommend a gluten-free diet for people with IBD.

Thinking about trying a gluten-free diet? Here’s what you need to know.

Gluten and IBD: What’s the Connection?

Researchers have long suspected a link between celiac disease — an immune reaction to eating gluten — and IBD. One analysis, published in May 2020 in the journal Gastroenterology, found that people with celiac disease are 9 times more likely to have IBD than people without celiac.

“Both celiac disease and IBD are autoimmune diseases. Sometimes, when there is chronic inflammation and autoimmunity, people could tend to have more than one condition,” explains Marvin Singh, MD, an integrative gastroenterologist and founder of Precisione Clinic, in Encinitas, California, which specializes in personalized medicine.

When a person with celiac disease consumes gluten, an immune response is triggered in the small intestine. This can result in bloating, constipation, diarrhea, nausea, and vomiting, as well as fatigue and weight loss. Considering IBD also causes many of these symptoms, it’s easy to see how poorly managed celiac disease could make a person’s GI symptoms worse.

But, what about people like Hanks and others with IBD who don’t have celiac disease? Even without a celiac diagnosis, it’s still possible to have a gluten sensitivity or intolerance, which experts call non-celiac gluten sensitivity (NCGS). For those with NCGS, consuming gluten can still trigger symptoms such as abdominal pain, bloating, constipation, and diarrhea, as well as headaches, feeling foggy, and rashes, according to Mayo Clinic.

For people with IBD and NCGS, “Eating gluten can cause them GI distress or increase their symptoms,” says Dr. Singh. The problem is, there’s no test to diagnose NCGS, says the American Academy of Allergy, Asthma & Immunology. So, determining whether you have it amounts to cutting out gluten and seeing how it makes you feel.

Can Going Gluten Free Ease Your IBD Symptoms?

While there’s no cure for IBD, cutting out gluten may be a helpful part of symptom management for some people.

If you have IBD and celiac disease, you should eliminate gluten from your diet. It won’t make your IBD go away, Singh explains, but it will help reduce inflammation in your small intestine, which in turn should offer some improvement in your GI symptoms.

The answer for people who have IBD but not celiac disease is less clear. While the evidence hasn’t definitively shown that gluten worsens IBD symptoms, most people with IBD find that certain foods tend to trigger flare-ups. Cutting those irritants out of your diet can go a long way toward helping you feel better, according to the Crohn’s & Colitis Foundation.

For some people, gluten might be one of those irritants. According to a review published in February 2022, nearly 40 percent of patients with IBD reported having less frequent or less severe symptoms while on a gluten-free diet, and nearly 24 percent needed fewer medications to control their IBD. Other small studies have also noted self-reported improvements in symptoms, but in some cases, researchers haven’t been able to measure or explain the improvement, according to a review published in April 2021 in the journal Intestinal Research.

In other words, there’s some research that supports a connection between a gluten-free diet and improved IBD symptoms in people without celiac disease, and plenty of individuals have noticed an improvement. But, for now, the evidence isn’t nearly robust enough to recommend that everyone with IBD stop eating gluten.

Going Gluten Free With IBD

If you don’t have celiac disease but suspect gluten could be triggering your IBD symptoms, there’s no harm in trying a gluten-free diet to see if it helps.

You’ll need to take careful steps to make sure you’re avoiding gluten completely for a set amount of time to truly understand whether it triggers your symptoms, though, Singh explains. It’ll likely take at least two weeks of eating gluten free to notice any potential benefits. “Many will need a longer period — like four to six weeks,” he says.

Before cutting out gluten, get the green light from your gastroenterologist and see a dietitian who specializes in IBD, Singh recommends. These experts can help you identify the sources of gluten in your diet and help you learn to read food labels to find less obvious sources of gluten, such as packaged sauces and salad dressings. They can also help you fill in any nutritional gaps in your diet that might come from cutting out gluten-containing foods, such as wheat-based pasta or bread.

In some cases, people with a mild gluten intolerance are eventually able to reintroduce gluten into their diets in small amounts without a problem. “It depends how sensitive you are,” Singh says. “Oftentimes, people might be able to tolerate a little bit of something, but when they cross the threshold of the amount they can take, they get symptomatic.”