Forest

What is the forest microbiome?
• The forest microbiome consists of microorganisms in soil, plants, and air, including bacteria, fungi, and other tiny life forms.
• When we walk in the forest, we inhale and absorb these microbes through our skin and lungs.
• Forest soil contains a much richer microbial diversity than urban environments.

How does it affect mood and mental health?

1. Through the immune system
• Exposure to diverse microbes strengthens the immune system.
• A balanced immune system is linked to better mood regulation and lower inflammation, which may reduce depression risk.

2. Stress reduction
• Forest microbes can influence the gut microbiota, which in turn affects brain chemicals like serotonin.
• Studies show that spending time in nature lowers cortisol levels (the stress hormone) and reduces blood pressure.

3. Immediate calming effect
• The combination of microbes, green scenery, silence, and natural scents activates brain areas related to relaxation and pleasure.
• Just 20 minutes in a forest can significantly boost mood and reduce anxiety.

Scientific evidence
• Tytti Pasanen’s doctoral research (Yle, 2020) showed that being in nature improves mood regardless of the activity.
• A Duodecim journal review emphasized that forest exposure may be a valuable public health tool for preventing mental health issues.
• Green Care methods use forest microbiomes as part of therapy and rehabilitation in Finland.

Practical tip
• Walk slowly in the forest, touch trees, sit on moss – all of these increase microbial exposure.
• Avoid using disinfectants immediately after your forest walk – let the microbes do their magic!