At this point, research is promising about the potential effects of prebiotics for IBD, but there isn’t enough data yet — especially in humans — to link increased use to definite benefits, says Dr. Dibba.
“What we have now is not sufficient enough to prove that prebiotics are associated with specific treatment of gastrointestinal illnesses,” she says.
“However, when those prebiotics are obtained from whole foods like fruits, vegetables, and legumes, this can promote overall health and increase intake of vitamins and minerals, which can help with digestion and bowel regularity.”
Potential Health Benefits
Preliminary research shows some promising results: One research review notes that in studies on animals, prebiotics lessened the severity and symptoms of a UC-like disease. In small studies with humans, one showed a change in the microbiome’s makeup, and another found that participants’ inflammation markers and symptoms were reduced. But the authors also write that, while measurements of disease activity and relapse rates might decrease with the use of prebiotics, the high number of participants who withdrew from supplementation studies indicates that the side effects may not be tolerable for some people.
“Further research is needed, but we do know that when focusing on an approach like the Mediterranean diet, which includes some prebiotics, it has the potential to help those with IBD,” says Dibba.
Potential Health Risks
Research suggests that higher intake of dietary fiber is connected to a significantly lower risk of flares in Crohn’s.
But some types of fiber can cause temporary discomfort, says Baumohl. That’s because not all dietary fibers are tolerated equally.
“Certain prebiotics found in foods like garlic, onions, beans, and wheat are broken down very quickly by bacteria,” she says. “This rapid breakdown can produce significant gas and bloating.
However, this is not a sign your IBD is getting worse; it’s just an indication that your gut is working hard to process those specific foods. There are strategies for introducing these foods into your diet while minimizing discomfort.”
Some preliminary research, however, including a small trial with 18 healthy people and a separate study on mice with an animal model of IBD, has found that the prebiotic fiber inulin can trigger inflammation. The mice with IBD-like illness experienced inflammation in their intestines when given inulin, while the human study participants had inflammation throughout their bodies — except for one participant who experienced a reduction in overall inflammation. Further research on human tissue, blood, and stool samples suggests an inflammatory process similar to what the mice experienced is primed in people with IBD, and dietary inulin could worsen the illness.
Inulin is sold in supplement form as a prebiotic. It’s also commonly added to foods and drinks as a prebiotic fiber, or as a replacement for fat or sugar. It’s in products as varied as soy-based drinks, instant coffee, baked goods, pasta, snack bars, cheese, yogurt, ice cream, and meats, so read nutrition labels closely if you opt to avoid it.