Like fingerprints and the patterns in the irises of our eyes, each of us has a unique microbe signature – more intricate than we might imagine. Microbiologist Dr Brett Finlay says:
There are far more bacteria on Earth than there are stars in the sky, and despite their microscopic size, the Earth’s microbes weigh more than all plants and animals combined… the human body contains trillions of bacterial cells – most of which reside in your gut. For every one of your human genes, there are roughly 100 bacterial genes; some estimates are as high as 500.
In other words, we are more bacteria than human DNA! Where this becomes juicy (and helpful!) is that scientists are starting to discern microbe signatures in certain diseases. A study group in Vienna let by internist and psychotherapist Gabriele Moser examined the stool samples of people with stress-based irritable bowel syndrome (IBS) in conjunction with questionnaires on stress. They uncovered a correlation between gut bacteria and stress, depression and/or anxiety. Some medical experts refer to the gut as the second brain. It has its own nervous system, as intricate as the spinal cord, and there is evidence of two-way communication between the brain and the gut.
Irritable bowel syndrome affects between 10 and 20% of the Western world. IBS is not a single disease but is defined by a set of symptoms: abdominal pain, bloating, constipation and diarrhoea. The underlying cause varies from patient to patient and is often difficult to pinpoint. This means there is no single treatment for IBS. Some patients respond to dietary changes, some from probiotics although others find their symptoms aggravated by certain probiotics; some benefit from psychiatric drugs that alleviate anxiety and/or depression, and others by making lifestyle changes that reduce stress.
Considering that the surface area of the small intestine, where food is absorbed, is about the size of a tennis court, and that about 60% of our immune system is found there, it’s evident gut health requires further attention. There is extensive research looking at microbiome diversity and IBS and trials are underway. The medical world deepening our analysis of microbe signatures and decipher the messages transmitted between the gut and the brain. A good place to start is by increasing our gut microbiome through making sure we have enough prebiotic fibre and exposure to healthy probiotic sources from freshly fermented foods.