A quick and easy, non-invasive breath test could help hundreds of thousands of patients who have been diagnosed with irritable bowel syndrome (IBS). IBS affects more than four million people in the UK, but it is estimated that one in five of those diagnosed with IBS may have the more simple to treat condition known as Small Intestinal Bacterial Overgrowth (SIBO). The condition produces symptoms similar to IBS and is caused by having too much bacteria in the gut.