Could Gut Bacteria Cause Your IBS?

A researcher from Cedars-Sinai has used bacterial cultures to link IBS to an overgrowth of bacteria in the gut.

The study, published in the May 2012 issue of Digestive Diseases and Science, supports previous findings from clinical trials that antibiotics are an effective treatment for IBS.

Though recent studies have suggested that small intestinal bacterial overgrowth (SIBO) plays a role in IBS, there was no definitive link between IBS and gut bacteria.

According to a press release from Cedars-Sinai, the study examined samples of patients' small bowel cultures to confirm the presence of SIBO in more than 320 subjects. In patients with IBS, more than a third were also diagnosed with SIBO, compared to fewer than 10 percent of those without the disorder. Of those with diarrhea-predominant IBS, 60 percent also had bacterial overgrowth.

"While we found compelling evidence in the past that bacterial overgrowth is a contributing cause of IBS, making this link through bacterial cultures is the gold standard of diagnosis," Mark Pimentel, MD, director of the Cedars-Sinai GI Motility Program and an author of the study said in a press release. "This clear evidence of the role bacteria play in the disease underscores our clinical trial findings, which show that antibiotics are a successful treatment for IBS."

What About Diet and IBS?

Given this new science, should you change the way you've been eating? Does it matter if bacteria is to blame?

Pimentel says that, in the past, treatment for IBS has been focused on alleviating symptoms. Since this study confirms that bacteria is a key contributor, it makes antibiotics a possible course of treatment that may relieve symptoms even after patients stop taking the medication.

However, maintaining healthy gut balance should still be a priority in managing IBS. Here are a few ways to promote a healthy gut bacteria balance:

Enjoy a daily glass of red wine. A Spanish study found that participants who drank about nine ounces of Merlot or a low-alcohol red wine every day had improved bacteria balance in the colon.

Choose yogurts wisely. Yogurts with active live cultures, such as Lactobacillus and Bifidobacterium, help boost the good bug count in your belly.

Add some fermented foods. Fermented foods, such as kefir, sauerkraut, and miso, can improve gut flora in the intestines.

Get your fill of fiber, especially if your IBS symptoms present as constipation. Choose whole grains, and include cooked vegetables and fruit in your daily diet. You can increase fiber by sprinkling flax seed on cereal, salad, or yogurt.

As always, any changes in bowel movements should be discussed with your doctor.




Press Release. Cedars-Sinai physician definitively links irritable bowel syndrome (IBS) and bacteria in gut.

María Isabel Queipo-Ortuño, María Boto-Ordóñez, Mora Murri, Juan Miguel Gomez-Zumaquero, Mercedes Clemente-Postigo, Ramon Estruch, Fernando Cardona Diaz, Cristina Andrés-Lacueva, and Francisco J Tinahones.  Influence of red wine polyphenols and ethanol on the gut microbiota ecology and biochemical biomarkers. The American Journal of Clinical Nutrition.