Ulcerative Colitis and Probiotics

A growing number of people with ulcerative colitis are reaching for probiotics -- products containing so-called "friendly" bacteria that populate the intestines.

Why? Researchers don't yet know what causes ulcerative colitis and other inflammatory bowel diseases (IBD). So finding effective treatments has been a challenge. Several kinds of medications can help reduce inflammation, improve symptoms, and achieve remission. But many people with IBD also want to use more natural methods to ease their discomfort.

Two out of five patients with inflammatory bowel disease use probiotics regularly, recent surveys suggest.  Children with IBD are also frequently given probiotics by their parents.

But do they really work?

"I'm a great believer in probiotics," says Walter J. Coyle, MD, director of the Gastrointestinal Program at Scripps Clinic Medical Center in La Jolla, Calif.  "I definitely recommend them for irritable bowel syndrome, regulation, and bloating. But frankly, when it comes to inflammatory bowel diseases like ulcerative colitis, we have almost no scientific evidence that they are beneficial."

Probiotics and Ulcerative Colitis: A Mixed Bag of Findings

In theory, at least, the approach makes sense. Ulcerative colitis and other IBDs may occur when bad bacteria outnumber the beneficial bacteria that normally reside in the gut. Recent research suggests that a lack of certain beneficial bacteria may also be a cause of the diseases. If that's true, introducing more friendly bugs would certainly seem to help.

Evidence Supporting Probiotics for Ulcerative Colitis

Researchers have discovered probiotic bacteria can influence the activity of immune cells and the cells that line the intestines. Specifically, these friendly bacteria appear to block disease-causing bacteria from sticking to the lining of the intestines. There's also evidence that the good bugs block chemical factors involved in inflammation.

"It's clear that the effects of probiotic organisms could be helpful in treating the pathogenic mechanisms of inflammatory bowel disease," notes University of Alberta gastroenterologist Richard Neil Fedorak, MD, who recently published a review of current research findings on probiotics.

Murky Results in Some Clinical Trials of Probiotics

Still, researchers acknowledge that they're only just beginning to explore the complex populations of bacteria -- friendly and unfriendly -- that reside in the gut. So far, clinical studies designed to test whether probiotics help either to maintain remissions or to resolve flare-ups have produced murky results.

For example, a randomized controlled trial with 90 volunteers found significantly higher remission rates in people with ulcerative colitis who were given the beneficial bacteria E. coli Nissle. The higher the dose, the longer their remission -- good evidence that the friendly bacteria were effective. 

But other studies that looked at other bacteria haven't shown any benefits compared to placebos. A 2006 study of 157 ulcerative colitis patients found no difference between the placebo group and those given one of three different beneficial bacteria, although the findings did suggest that probiotics may have prolonged the length of remission.