What your rumbling tummy is really telling you

It could be hunger pangs, but a revolutionary new microphone may also reveal whether it’s a sign you have Irritable Bowel Syndrome

With Christmas just around the corner we will soon be scoffing lots of rich foods, which will make our tummies rumble even more than usual.

those grumbling, growling noises are the result of food, liquid, and gas passing through your stomach and into your small intestine. there is even a name for it, Borborygmi, a term coined more than 2,000 years ago by hippocrates, an ancient Greek, also known as the Father of Modern Medicine.

And now scientists have shown that these sounds can reveal insights into what is going on in the gut and may help diagnose common disorders.

At least 15 million Britons have digestive problems, with around one in five of us suffering from the UK’s most common gut disorder: irritable Bowel Syndrome, or iBS. Symptoms include pain, bloating, and either constipation or diarrhoea.

Diagnosing iBS can be a lengthy and challenging process — as there is no specific test, doctors can only rule other things out, and as a result iBS may be missed or other conditions overlooked.

So imagine how great it would be if you could make a diagnosis by listening to stomach noises.

Well, that is what an old friend of mine, Professor Barry Marshall, who is based at the University of Western Australia, is working on. Barry has created a machine you strap to your abdomen, which listens to your gut noises, then analyses what is going on inside, a bit like a high-tech stethoscope.

ProFeSSor Marshall is one of my scientific heroes. Back in the 1980s he deliberately infected himself with a dangerous bacterium, called helicobacter pylori, to prove that it is the leading cause of gut ulcers. i celebrated loudly when he and his colleague, robin Warren, won the Nobel Prize for Medicine in 2005.

Now Barry has turned his fertile mind to gut sounds. ‘i thought why not put microphones on people’s abdomens and analyse the sounds they make with artificial intelligence,’ he told me, ‘because i was sure that common gut problems must be related to contractions in the guts.’

‘the Noisy Guts Project’ began with a chance encounter with a friend who showed Barry some small, super-sensitive microphones he was using to study the sound termites make as they chomp their way through people’s houses.

Barry realised that these microphones were exactly what he needed to listen to stomach noises. So he put together a team, and using similar microphones they built devices which could be strapped on to people’s stomachs to listen to and analyse gurglings. A subsequent trial found that this method could pick up around 87 per cent of patients with iBS.

they are now busy putting together a database of stomach noises to try to make their devices even more accurate, and not just in diagnosing iBS. A few weeks ago Barry’s team began recruiting patients with other common gut conditions, including Crohn’s disease, ulcerative colitis and coeliac disease, for clinical trials of this technology.

they hope to show that listening to gut noises could save people from invasive and time-consuming colonoscopies, where a camera is inserted into the bowel. Given the option of that or a recording being made of my rumbling tum i know which one i’d choose. once diagnosed, the only really effective treatment for most cases of iBS is a low FoDMAP diet. FoDMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols.

these are types of carbohydrate, found in foods such as garlic, onions, apples, milk, yoghurt and chickpeas, that are normally considered healthy, but if you have iBS can trigger symptoms.

You begin by eliminating FoDMAPs, then gradually reintroduce some of these foods to see which ones are causing your problems; these are then eliminated from your diet. Clinical trials have shown doing this improves symptoms in around threequarters of iBS patients.

More recently, a trial, carried out by researchers at King’s College London, showed that going on a low FoDMAP diet may also help patients with Crohn’s disease and ulcerative colitis, both of which are caused by inflammation in the gut.

heartening news — but adhering to a low FoDMAP diet is complicated, so it is best done with the help of a qualified dietitian.