Protecting the Gut With Prebiotics: Researchers Explore Inulin to Treat IBD

Researchers are studying whether the prebiotic fiber, inulin, can have beneficial effects for individuals with IBD.

By Jillian Rose Lim

Our gut microbiome, that complex community of healthy and sometimes harmful bacteria, plays a big part in our health, from regulating the immune system to influencing everything from digestion to depression. In recent years, scientists have drawn links between the microbiome and inflammatory bowel disease (IBD), one of the most significant chronic conditions affecting children and adolescents today. A microbiome lacking beneficial bacteria can trigger the inflammation characteristic of IBD, while one packed with protective bacteria may control it.

Treating IBD differs for each patient, but one thing researchers are sure of is that diet — particularly one rich in fiber — is one of the biggest determinants of a good, healthy gut.

At Children’s Hospital of Philadelphia, Jessica Breton, MD, is studying how a particular fiber, inulin, might improve the microbiome of patients with IBD and potentially treat or even prevent the disease. Studies working with animal models and adults have shown that inulin, like other fibers, has an anti-inflammatory effect in the gut. But unlike previous studies, Dr. Breton’s research is the first to look specifically at inulin’s effect in pediatric IBD.

“We know fibers are really important for a healthy gut microbiome because it increases the proliferation of the good protective bacteria, which we know patients with IBD lack,” said Dr. Breton, an attending physician in the Division of Gastroenterology, Hepatology, and Nutrition at CHOP. “The overarching goal of this study is to see whether by providing fiber supplements, we can change the microbiome in a way that has an anti-inflammatory effect that can help treat the disease.”

Dr. Breton’s team will conduct the study remotely, shipping fiber supplements directly to participants’ homes and requiring no hospital visits or face-to-face contact. Because the inulin provided is in a tasteless and unscented powder form, Dr. Breton believes participants or their parents will likely find it easy to incorporate into meals. They can sprinkle a teaspoon into yogurt or a smoothie, for example.

But to recognize how such a supplement might support patients with IBD in the future, it helps to understand how inulin works in our bodies. Inulin is a prebiotic soluble fiber, which means that it feeds and nourishes the protective bacteria in the gut. When fermented (or broken down) by bacteria in the large intestine, it produces metabolites. One main type of metabolite that’s produced are short-chain fatty acids (SCFAs), and among these is a particular SCFA called butyrate.

Studies suggest butyrate plays a vital role in gut health: It helps feed the cells of our gut lining so they stay healthy and strong, it controls inflammation, and overall, it improves the gut’s homeostasis.

Children with IBD have been shown to eat a highly Americanized diet, high in processed foods and refined sugar, but low in fiber and good bacteria. So, when paired with what we know about the gut of individuals with IBD, inulin is a perfect candidate to study.

“If you look at gut metabolites of individuals with IBD, they tend to have reduced butyrate levels,” Dr. Breton said. “Inulin, by virtue of increasing butyrate, may help the disease, and that’s the premise of this research.”

If the study indeed shows inulin has a noted influence on inflammation, Dr. Breton looks forward to taking the next step in her research. Currently, however, she and her team are still gathering patients with IBD, ages 8 to 21 years and in clinical remission, to participate.

“This is just the first step; it's a proof of concept,” Dr. Breton said. “Right now, we're recruiting patients in clinical remission but with high inflammatory markers. And if we can show that the inulin actually modulates the patients’ microbiome, then the next step will be to use it in patients with active disease, in a trial as a treatment.”

In the meantime, Dr. Breton is enthusiastic about exploring the microbiome — an exciting field in IBD research thanks to increasingly expanding knowledge of its impact.

“To me, the microbiome is definitely a field with a lot of promise for this patient population,” she said. “And though we now have more immunosuppressive therapies for IBD with the advent of biologic therapy, those therapies aren’t perfect. There are still some patients who are refractory, and we definitely have yet to find a cure for this disease. So, by studying the microbiome, my hope is that we can find alternative or adjuvant treatments that can work with our immunosuppressive therapy. Maybe in the future, we'll be able to modulate the microbiome so then we can even prevent the initiation of this disease or even cure it.”

Learn more about Dr. Breton’s IBD/inulin study and how you or your child might participate.