A patient’s gut may not be the most obvious place to look for the origins of depression. Scientists have discovered the power of our gut microbiota to harm or heal, but the notion that they could be responsible for our mental health is perhaps the most difficult to grasp. How could these microscopic scavengers, feeding on the debris of our digestion, possibly affect the brain?
The fundamental idea of a gut-brain axis is now remarkably solid, according to a BBC.com feature. “There is no debate, in my mind, that microbes influence mental health,” says Jane Allyson Foster, whose lab at McMaster University in Canada is leading research in this area. And that means we may be able to heal the brain through the belly. “There is the potential both for the development of novel therapeutics and for precision medicine.”
Foster emphasises that an unhealthy gut is just one of many possible causes of mental illness, meaning that only a subset of patients will respond well to the new “psychobiotic” treatments. But for those patients who are suffering from an imbalance in their gut bacteria, the new therapies might bring much-needed relief.
Certain species of gut microbes can protect the gut wall – helping to maintain its mucous membrane that stops the contents spilling into the blood stream. Gut microbes also influence how we digest and metabolise the precursors of important neurotransmitters like serotonin and dopamine.
A panacea for depression is difficult to propose, but for some people at least, a healthier digestive system may be an important first step to a healthier and happier mind.