We're getting less shy about talking about our bowels these days. That can only be a good thing; in a country with one of the highest rates of bowel cancer, the more we can normalise conversations about the workings of our guts, the better.

But by far the most common gastrointestinal disorder is something less serious but no less worrying for sufferers: IBS, or Irritable Bowel Syndrome.

IBS is what's known as a functional gut disorder. That means there's nothing physically wrong in the gut – nothing doctors can see. It tends to be diagnosed after a process of elimination;