What Is Irritable Bowel Syndrome?

Irritable bowel syndrome (IBS) is a common condition characterized by “gut symptoms” inclusive of abdominal pain, discomfort, bloating, distention and increased gas production associated with concurrent changes in the frequency or consistency/texture of stool. IBS affects 10 to 15 percent of the world’s population, and it is two times more common in women than in men. This disorder usually impacts younger individuals between their teen years to their 40s.

IBS is commonly broken into three major subcategories: IBS with diarrhea (IBS-D), IBS with constipation (IBS-C), and mixed IBS (IBS-M) which represents a combination of IBS-D and IBS-C. Interestingly, some people may change from one subtype to another over time.

Currently there are no cures for IBS but multiple different treatment modalities ranging from standard pharmaceuticals, to more complimentary treatments like peppermint oils, and behavioral therapies exist and are supported by good evidence-based clinical trials.

While many consider IBS to be a diagnosis of exclusion or a “coverall” for common GI symptoms, in truth, the diagnosis of IBS is made using an established set of criteria with high accuracy, thus, mitigating the need for extensive testing in most individuals.   

Recent research indicates that IBS is a heterogeneous disorder with many potential causes leading to similar symptom profiles.  Historically considered a disorder of brain-gut dysregulation, symptoms may be related to hyperactive nerves in the wall of the gastrointestinal tract associated with changes in how the brain processes information received from these nerves.

Other potential causes for IBS include but are not limited to modification in an individual’s genetics, environmental triggers like infections, alterations in the bacteria in our GI tracts, food, bile-acid malabsorption, and small intestinal bacterial overgrowth.

Irritable bowel syndrome (IBS) is sometimes confused with inflammatory bowel disease (IBD), an illness that includes Crohn's disease and ulcerative colitis. Unlike Crohn's disease and ulcerative colitis, IBS doesn’t cause changes in bowel tissue or increase your chances of developing colorectal cancer. A small percentage of individuals may experience symptoms of both IBS and IBD at the same time.