SCIENTISTS HAVE DISCOVERED A NEW HIDDEN GUT ‘SENSE’ THAT COULD REVEAL JUST HOW MUCH GUT HEALTH INFLUENCES OUR BEHAVIOUR

More and more of us are focusing on our gut health: eating foods that will benefit our gut microbiome and paying attention to how our sleep and stress levels can impact the way it works. If you’ve ever read around the topic, you’ll know that research into how exactly our gut operates and the impact it has on a whole range of bodily processes is extremely new scientific territory. This means fresh discoveries about this part of our anatomy are being uncovered every day.

The gut-brain axis is particularly exciting. Researchers are just starting to scratch the surface of what is possible when it comes to the signals that pass between our digestive system and central nervous system, and how this can influence everything from our concentration to our mood. Now, a new study has uncovered a “breakthrough” piece of research that could provide an even deeper insight into how gut microbes shape our behaviour and mental health.

The study, led by Duke University School of Medicine and published in Nature this week, examined neuropods, aka the tiny sensor cells that line our colon, and found that these cells hold a hidden “neurobiotic sense” that sends messages to the brain when they detect a specific form of microbial protein called flagellin, which is found in bacterial flagella.

The study found that when we eat, some gut bacteria release flagellin, the neuropods detect it and then using a receptor called TLR5, they fire a message through the body’s vagus nerve – a major communication line between the gut and the brain.

However, the researchers wanted to understand exactly how influential this neurobiotic sense could be, including how it could influence our eating habits and mood — and even how the brain might shape the microbiome in return.

The study fasted mice overnight and gave these mice a small dose of flagellin directly to the colon. It found that the mice ate less. When researchers trialled the same experiment in mice which did not have a TLR5 receptor, these mice continued eating. The scientists used this evidence to conclude that flagellin sends a signal through the TLR5 that tells the brain the body is satiated and doesn’t want to anymore to eat. When this receptor is missing, this signal doesn’t reach the brain.

While we should always be sceptical about how much we can apply studies performed on rodents to the human body, the findings suggest that this neurobiotic sense does indeed send signals to the brain, which has far wider implications about how much impact our gut could have on everything from our behaviour to our emotions. We already have a limited understanding of these gut-neural pathways, but this research further solidifies just how critical the gut-brain axis could be when it comes to our wellbeing. 

“Looking ahead, I think this work will be especially helpful for the broader scientific community to explain how our behaviour is influenced by microbes,” said Dr Diego Bohórquez, a neuroscientist at Duke University School of Medicine. 

Images: Getty

2025-08-07T15:48:10Z