Could the microbes living in soil have an impact on human emotions, relationships, and even feelings of love?
Scientists from Flinders University in Australia think it’s possible.
They’ve published a new review in mSystems suggesting that the tiny organisms in soil may play a surprising role in shaping our hormones and brain chemistry, which in turn affect how we feel and connect with others.
Dr. Jake Robinson, together with colleagues Ondi Crino, Associate Professor Martin Breed, and UK neuroscientist Araceli Camargo, explored how microbes could influence hormones such as dopamine, serotonin, and oxytocin—the very chemicals linked to happiness, bonding, and affection.
“We’re not saying microbes directly cause love,” Dr. Robinson explains.
“But we want to highlight the biological pathways where microbes might influence emotions that are central to love and social bonds. These ideas now need to be tested through careful human studies.”
Their paper, titled Does a microbial-endocrine interplay shape love-associated emotions in humans? A hypothesis, suggests that the gut microbiome—the vast community of microbes inside our digestive system—might communicate with the brain through what’s known as the “gut-brain axis.”
This connection could affect not just positive emotions like love, but also negative ones such as hate and aggression. If confirmed, the findings could help develop new strategies for improving mental health and strengthening relationships.
The researchers also looked beyond the human body to the wider environment, focusing on soil as an important piece of the puzzle. Healthy soils, they point out, don’t just grow plants.
They also release important chemical and microbial signals that may benefit human health.
According to Associate Professor Breed, soils support vegetation that can clean the air, reduce noise, and help regulate local temperatures—all factors that influence our nervous, immune, and hormonal systems. On the other hand, when soils degrade, they may produce more harmful particles and lose microbial richness, with possible negative impacts on mental well-being.
Dr. Robinson, who has written several books about ecology including Invisible Friends and Treewilding, is also launching a new initiative to promote soil health and raise awareness of how food systems connect to human health.
His team’s work extends to global studies as well. In a recent project published in Nature Cities, Robinson and Breed measured soil biodiversity in urban green spaces across 13 cities in China.
They found that while cities can increase soil biodiversity locally, they also make soils more similar across regions, which can weaken large-scale stability.
The research team argues that protecting and restoring soils should be part of urban planning, public health, and environmental policies.
By creating environments that are not only green but also rich in healthy microbes, societies might foster both ecological resilience and human well-being.
It’s a reminder that our emotions and relationships may be influenced not just by our bodies and minds, but also by the ground beneath our feet.
