โน also click on the links ๐..longer..
"I read studies that show that forests๐ณ๐ณ๐ณ are full of airborne bacteria that, when inhaled, can actually reach your gut and lungs ๐ซ influencing serotonin, dopamine, and your stress response.
So that deep breath you take in the woods,
It’s not just oxygen - it’s a microbial upgrade ๐ฆ Your body is literally reconnecting with the microscopic world it evolved with, and that interaction reduce cortisol and lift your mood ☺️"
by Gil Alter (Thank you)
"About "forest bathing" (Shinrin-yoku) and the "gut-brain axis".
Breathing forest air is more than just oxygen; it is an exposure to a diverse "microbial cloud".
Forests and natural environments are full of bacteria in the air (bioaerosols) originating from soil, plants, and trees. When you breathe deeply, you inhale these diverse, non-pathogenic (harmless) bacteria.
They can enrich their own microbial population via the lungs and intestines, which is seen as an 'upgrade' of your microbiome.
Not only does forest air contain phytoncides, natural antimicrobial oils that trees can secrete to defend themselves against bacteria and fungi, which, when inhaled, increase the activity of human 'natural killer' cells, thereby strengthening immunity, lowering stress hormones, and reducing blood pressure, but
The deciduous forest and nature are also essential for our health.
Whereas phytoncides act directly on our NK cells, the microbial world provides long-term "training" of our immune system.
Below are the most important scientific insights into the microbial world in forests and nature:
1. Training of the immune system (Immunomodulation)
Exposure to forest microbes, especially in the soil and on leaves, triggers a positive chain reaction.
* Immune training:
Direct contact with various soil bacteria (such as via the skin or inhalation of dust particles) increases the presence of regulatory T-cells. This helps the body distinguish between dangerous pathogens and harmless substances, which reduces the risk of allergies and autoimmune diseases.
* Skin microbiome:
Research shows that people in a biodiverse green environment have a greater variety of microbiota on their skin. These "good" bacteria form a physical barrier against harmful invaders.
2. Mycobacterium vaccae: The "happy bacteria"
The bacterium Mycobacterium vaccae is found in the soil of healthy deciduous forests. Scientific research suggests that exposure to this microbe:
* Stimulates the production of serotonin in the brain, which reduces stress and improves mood.
Research shows that exposure to a diverse natural environment changes the gut microbiota. Certain bacteria from nature (such as Lactobacillus and Bifidobacterium species) can stimulate the production of neurotransmitters in the gut, including serotonin and dopamine.
Since more than 90% of the serotonin in your body is produced in the gut, this directly influences your mood and emotional stability.
* Can suppress inflammatory responses in the body.
A walk in the woods demonstrably lowers cortisol levels (the primary stress hormone) in the blood.
In addition to bacteria, you also inhale phytoncides – aromatic substances secreted by trees – which activate the parasympathetic nervous system (the 'rest-and-digest' mode) and lower blood pressure.
3. The "rich litter" effect of deciduous forests
Deciduous forests have a specific microbial dynamic that differs from coniferous forests:
* Rapid digestion:
Leaves of deciduous trees form "nutrient-rich litter" that decomposes easily and creates an extremely nutrient-rich soil. This attracts a completely different diversity of bacteria and fungi than the acidic soil under conifers.
* Bio-aerosol:
While walking, these microbes swirl up in the air. Inhaling this "microbial cocktail" contributes to a healthier gut microbiome and increased immunity.
4. The Finnish "Playground Study"
A well-known study from Finland (Roslund et al., 2022) simulated the effects of a forest floor on children. After only 28 days of playing in sand enriched with forest microbes (from deciduous and mixed forests), the children showed:
* Higher microbial diversity on the skin and in the intestines.
* Elevated levels of anti-inflammatory proteins in their blood.
Evolution and Reconnection:
Humans evolved in a bacterial, natural environment. The modern, sterile urban lifestyle has led to an impoverished microbiome, which is linked to inflammation and mental health issues. The forest acts as a 'reset', allowing your body to reconnect with the microbial world with which it evolved.
In short: deep breathing in nature is an effective, natural way to support your immune system, gut health, and mental well-being.
And then we must not forget the effect of grounding and the negative ions of the natural environment either: https://jesseversteghen.blogspot.com/p/electroculture-or-electron-culture.html
Wishing you good health ๐.
Jesse.
Scientific Sources:
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A Breath of Fresh Air: Perspectives on Inhaled Nutrients and ... - PMC
Although the health benefits of fresh air in natural spaces are partly because of a reduction in airborne industrial pollutants, additional benefits may come fr...
National Institutes of Health (.gov)
Airborne bacterial communities of outdoor environments and their ...
Highlights. • Studies have revealed a wide diversity of bacteria in the atmosphere. Atmospheric factors regulating airborne bacterial communities need to be elu...
ScienceDirect.com
Impact of outdoor nature-related activities on gut microbiota, fecal ...
15 dec 2020 — Outdoor nature-related activities can enhance general well-being. However, the underlying mechanisms are not fully delineated. Here we recruited 54 preschool ch...
National Institutes of Health (.gov)
A Breath of Fresh Air: Perspectives on Inhaled Nutrients and Bacteria to ...
15 dec 2024 — Trayhurn asserted that “the route of entry should not be the critical factor in defining whether a substance is, or is not, a nutrient.” If we accept this defin...
ScienceDirect.com
Impact of outdoor nature-related activities on gut microbiota, fecal ...
15 dec 2020 — The increased exposure to natural environments and animals is an important determinant of individual gut microbiome25,26, skin microbiome27 and salivary microbi...
Nature
Our depleted gut flora is one of the reasons why we are faster to ...
14 Mar 2024 — ) such as serotonin, dopamine, and glutamate. If we have more or less of one type of bacteria, that can strongly change the conversion of dopamine and serotonin...
The Morning
Impact of Environmental Pollutants on Gut Microbiome and Mental Health ...
The co-evolution of human beings and their microbiota has emerged due to a symbiotic interplay and ัo-deัendenัy for both species' existence, ensuing in biomole...
PubMed Central (PMC) (.gov)
The correlation between gut microbiota and both ... - PMC - NIH
Translated — Moreover, it has been shown that specific bacterial genera in the gut microbiome, such as Escherichia, Enterococcus, Candida, and Streptococcus, produce serotonin ...
National Institutes of Health (.gov)
The role of the gut-brain axis in the regulation of dopaminergic signaling.
Translated — Therefore, Enterococcus faecium and Enterococcus faecalis, in combination with ฮฑ-fluoromethyltyrosine, may qualify as probiotics due to their potency...
PubMed Central (PMC) (.gov)
How Forest Air Shifts Your Brain Chemistry & Physiology
28 jul 2025 — Our respiratory system is lined with mucous membranes that protect against allergens, pathogens, and dryness. Humid air helps these membranes stay moist and fun...
Kona Cloud Forest Sanctuary
Why being outdoors makes you healthy and happy - Women's Health
Oct 5, 2020 — ... have when you have been digging in the earth, it isn't all in your head. Or well, having contact with the ground provides health benefits in your brain, you...
Women's Health Nederland
Does serotonin in the gut make you happy? - PMC - NIH
Translated — Of the total amount of serotonin in our body, 90% is synthesized by the argentaffin cells in the gastrointestinal tract. It is striking that only un...
PubMed Central (PMC) (.gov)
The Science Behind Forest Bathing
5 mrt 2025 — Stress Reduction: Phytoncides are believed to lower cortisol levels, the hormone associated with stress. By inhaling the fresh forest air, your body's stress re...
Friends of the Forest
A walk through the forest: a boost for your immune system
May 6, 2020 — A walk through the woods: a boost for your immune system.
zenADrelax
A WALK THROUGH THE FOREST MEANS A BOOST FOR ...
May 5, 2017 — What already felt that way instinctively is now confirmed in various scientific studies: a walk in nature is good for our physical and our psych...
www.natuurenmens.be "
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