“Irritable bowel syndrome (IBS) is the most common functional gastrointestinal (GI) disorder with worldwide prevalence rates ranging generally in the area of 10–15%. Functional GI disorders are disorders that occur because of abnormal functioning of the GI tract, which can affect motility, sensation, and brain–gut communication.”

International Foundation for Gastrointestinal Disorders – iffgd

(https://aboutibs.org/what-is-ibs/facts-about-ibs/statistics/)