While the science is still in its infancy, more and more pieces of research are confirming that humans need regular skin contact with soil to stay healthy and well; Hence our catch-phrase; ‘Get Dirty& Live Well’!

Many years ago-when I was a lad- I used to listen to a 1950s BBC radio show called ‘Beyond our Ken”. One of the regular players in the show was a fictitious gentleman called Arthur Fallowfield whose stock phrase (in a broad Somerset accent) was “I Think the Answer Lies in the Soil”.  Arthur’s phrase could not be more accurate.

1. Why Dirt Deserves a Health Halo

Modern life has scrubbed us clean—literally.
A soil-less city life, Antibacterial gels, concrete playgrounds and sterilised baby toys have slashed our daily contact with soil microbes just as chronic diseases like asthma, allergies, ADHD, depression) have surged- Coincidentally-or not!

Reconnecting with organic, living soil —the kind that smells earthy and crumbles in your hand— re-seeds your skin, gut and even brain with organisms we co-evolved with for 300 000 years.

2. What the New Studies Show

2.1 Immune & Allergic Diseases (asthma, eczema, coeliac, T1-diabetes)
– Finnish daycare trial: kids who played on forest-floor soil for 28 days had higher anti-inflammatory gene expression and richer gut microbiomes than peers on gravel yards; the benefit persisted 2 years .
– Mycobacterium vaccae , a common soil actinobacterium, dampens Th2 inflammation (the pathway that drives asthma and eczema) and increases regulatory T-cells in human blood within 2 h of skin contact .
– Meta-analysis of 23 cohorts: farm/soil exposure in first 3 years cuts later asthma risk by 31 % .

2.2 Neuro-developmental Conditions (Autism & ADHD traits)
– Mouse model of maternal immune activation (a risk factor for ASD-like behaviour): pups born to dams housed with sterilised farm soil showed less repetitive behaviour , better social ultrasonic vocalisations and lower IL-6 in hippocampus .
– Human pilot: 8-week gardening programme for teens with  developmental  issues→ The impact of an agro-healing program on family resilience, parental stress, and social skills of children with developmental disabilities – ScienceDirect

2.3 Mental Health & Stress Resilience
– Randomised trial: adults who mixed S. rimosus-rich soil for 20 min had ↑ frontal-lobe alpha waves (relaxation marker) and ↓ serum C-reactive protein versus sterile-soil controls .
– Functional-MRI study: same soil exposure quieted amygdala reactivity to social-stress imagery .
– Epidemiological: UK Biobank participants who garden ≥ 2 × week show 33 % lower odds of depression after adjustment for income, BMI and greenspace access .

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3. Mechanisms: How Soil Talks to Your Body

| Route | Key players | Effect |

| Skin | M. vaccae , S. rimosus , geosmin | Local anti-inflammatory signalling → systemic IL-10 ↑ |
| Gut | Soil-derived spores, actinobacteria | ↑ microbial diversity → ↑ butyrate → strengthens gut-blood-brain barrier |
| Olfactory | Geosmin, 2-MIB | Direct vagal stimulation → ↑ serotonin & dopamine |
| Nutrient | Soil-grown polyphenols, Mg, Zn | Cofactors for enzymes that synthesise 90 % of serotonin (in gut) |

4. Best-Practice “Soil Rx” (evidence-based)

1. Source : Use organic compost or forest topsoil —never potting mix with peat or synthetic fertiliser (it’s often sterile).
2. Frequency : Aim for ≥ 3 hand-soil contacts per week , each ≥ 10 min —the Finnish & Japanese dose that moves microbiome needles.
3. Method :
– Garden without gloves (wash lightly, no antibacterial soap).
– Let kids make mud pies; encourage face & arm dabs —skin colonisation matters.
– Bare-foot vegetable harvesting doubles microbial uptake through plant-root exudates.
4. Safety :
– Test soil for heavy metals if near old industry or roads.
– Cover open cuts; avoid cat-/dog-fouled sandpits.
– Take care to not inhale dust or bioaerosols from (particularly dry bagged) compost which can pose respiratory disease risks, particularly for individuals with weakened immune systems or pre-existing lung conditions. Pathogens like Legionella and fungi such as Aspergillus can be present in compost, potentially leading to infections like Legionnaires’ disease or aspergillosis.

Indoor option : Keep a small tray of living compost on the balcony; mix a tablespoon into house-plant soil and handle weekly.

5.  FAQ

Q: Can I just swallow a probiotic pill instead?
A: Pills supply 5–10 strains; one teaspoon of organic soil contains > 10 000 . Topical exposure also seeds skin microbiota , which oral pills miss .

Q: Does city park soil count?
A: Somewhat. Studies show microbial diversity rises 30 % even in urban green space, but forest or garden soils still outperform park turf .

Q: How soon will I feel different?
A: Mood lift can appear within one 20-min session (alpha-wave study) ; immune markers shift after ~3 weeks of regular contact .

6. Conclusion

“ Get dirty on purpose. Organic soil is the cheapest, safest immune-modulator and mood-booster we’ve forgotten to use.”

Roll up your sleeves, plunge your hands into compost, and let the planet doctor you!!

References (open-access links)
World Economic Forum – soil & human health (2024) https://www.weforum.org/stories/2024/10/soil-health-human-health-connection/

Nature Sci Rep – S. rimosus soil antidepressant effect (2025) https://www.nature.com/articles/s41598-025-13885-5

NYT “Get Dirty” review (2024) https://www.nytimes.com/2024/04/17/well/live/dirt-health-benefits.html

Psychology Today – soil & mental health (2024) https://www.psychologytoday.com/us/blog/a-subtle-impact/202408/what-does-soil-have-to-do-with-mental-health

Earth.Org soil-quality & malnutrition report (2024) https://earth.org/new-report-reveals-crucial-links-between-soil-quality-and-human-health-calls-for-global-action/

PMC psychophysiology study with S. rimosus (2022) https://pmc.ncbi.nlm.nih.gov/articles/PMC9564959/

Glowing Orchid – soil & skin microbiota (2024) https://glowingorchid.com/blogs/news/touching-soil-may-be-good-for-skin-and-health

Conscious Planet – soil & gut-brain axis (2025) https://consciousplanet.org/en/save-soil/news/getting-your-hands-in-soil

‘Good Nature-the new science of how Nature improves our Health’, Kathy Willis,Bloomsbury Publishing (2024)

To your earthly connection

Paul at ChangeThatMind.com

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