Is being in nature good for your gut?

Ever wondered why being in nature feels so good? In the last few years, science has started to explain why.

Beyond boosting your mood, spending time outdoors is increasingly linked to better physical health – particularly through its impact on the gut microbiome. Emerging research is uncovering a fascinating connection between the microbes in our bodies and those found in natural environments. 

What is a healthy gut microbiome?

Gut microbes are crucial in many aspects of human health. A healthy gut microbiome is a diverse and balanced community of microorganisms in the intestines that supports immunity, digestion and even mental health. Around 70–80% of our immune cells are present in the gut and research suggests that having more diverse gut microbiomes is associated with a lower risk of some chronic conditions including asthma¹ and heart disease². A key marker of good gut health is the diversity of microbiomes in your gut. 

How does being in nature improve your gut health?

When we spend time in nature, we are exposed to a wide variety of environmental microbes. They can be found in soils, plants, water and air. Interestingly, soil contains approximately the same number of active microorganisms per gram of material as the human gut.

Microbes from the environment can enter our body in several ways – through skin contact or even the food we eat. Once introduced, they diversify the gut microbiome and help outcompete microbes that carry disease such as viruses. 

Does being in nature benefit your mental health?

There is strong evidence that spending time in nature can support mental health. When viewed through the lens of gut health, the connection becomes more compelling. A diverse, healthy gut microbiome has been linked to improved mood and overall wellbeing. 

The gut-brain axis

This link exists because the gut and brain are closely connected through what’s known as the gut-brain axis. Trillions of microbes in our digestive system interact with the nervous system and produce many of the same neurochemicals, such as serotonin, dopamine and gamma-aminobutyric acid (GABA), that help regulate mood, sleep and emotion^10,11. They also influence inflammation and immune responses, both of which are linked to anxiety and depression. 

Can soil microbes improve mood?

Research has explored a soil bacterium called Mycobacterium vaccae which stimulates the release of serotonin when we’re exposed to it¹². This boost of serotonin acts as an antidepressant. Further research found that people living with cancer who were given a non-live version of the bacterium reported improvements in their quality of life. 

Another research project found that soil containing a microbe called Streptomyces rimosus is released in the air and inhaled by humans¹³. Researchers found that it can improve mood and reduce symptoms of depression by enhancing relaxation, reducing stress and changing body chemistry. While this area is still emerging, it points to another way our environment may influence how we feel. 

What are the threats to a healthy gut microbiome?

As populations become increasingly urbanised, our lifestyles are shifting further away from nature. It’s estimated that within the next few decades, around two-thirds of the global population will live in urban areas. This shift may limit our exposure to beneficial microbes and, in turn, influence the diversity of our gut microbiome.

Environmental microbial diversity itself is also under pressure. Soil health, for example, is degrading with industrial agricultural practices. Since soil is one of the richest sources of microbial life, changes to its composition could reduce the variety of beneficial microbes we encounter. While research on this is ongoing, scientists suggest that reduced exposure to diverse environmental microbes may be linked to changes in immune function, increased inflammation and a higher risk of certain chronic conditions. 

Nature as nourishment

The evidence is increasingly clear: spending time outdoors in biodiverse environments can positively influence our gut microbiome, immune system and mental wellbeing. These benefits have also been recognised by the NHS, which has introduced ‘green prescriptions’ to encourage people to connect with nature as part of improving mental and physical health. 

So the next time you’re walking through the woods, digging in the garden or simply sitting in the sun, remember these small moments in nature could be supporting your gut health.

At the same time, increasing urbanisation and reduced access to green space pose a growing challenge. By protecting, restoring and creating woods, we are protecting our own health.