Safeguarding Natural Ecosystems to Protect Health: An Interdisciplinary Review

A recent study by Murage, P., et al. (2025) explores a critical weakness of modern policy making: why we currently fail to see ecosystem restoration as a significant contributor to healthcare and boil it down to a mere "conservation goal".

By proposing a unified "Ecosystems Cascades Model," they demonstrate how ecological interventions—such as strategic tree planting—can be tracked directly to physiological outcomes, proving that safeguarding nature is not just conservation, but a vital medical intervention.

The Health-Ecology Divide

The Core Argument: While human health is intrinsically reliant on natural ecosystems for food, water, and disease regulation, the health sector has struggled to integrate ecological evidence into policy. Public health outcomes have improved globally, yet this progress often masks the degradation of the natural systems that sustain it.

Broader Context: This paper contributes directly to the growing field of Planetary Health, a discipline focused on the health of human civilization and the state of the natural systems on which it depends. It highlights a critical "silo" problem: public health research is traditionally bio-medical, while environmental sciences often fail to translate biodiversity data into metrics actionable for health policy.

The Conceptual Disconnect

The authors identify three major barriers preventing the integration of these fields:

• Opposing Focus: Environmental health disciplines (like epidemiology) typically view the environment as a source of hazards (e.g., arsenic, pollution, radon). In contrast, ecology views the environment as a source of services (e.g., climate regulation, crop pollination).

• Mismatched Scales: Health studies often prioritize immediate, localized risks (like air quality), whereas ecological degradation (like fish stock depletion) occurs over broad landscapes and long time horizons.

• The "Co-Benefits" Gap: External literature on Nature-based Solutions (NbS) often notes that while projects are designed for ecosystem restoration, their mental and physical health "co-benefits" are rarely measured simultaneously. This paper argues that this lack of measurement stems from the disciplinary divide.

Methodological Innovation: Merging Frameworks

To solve this, the authors propose merging two established frameworks to create a holistic "Theory of Change":

1. The DPSEEA Framework: A standard WHO tool (Driving Force-Pressure-State-Exposure-Effect-Action) traditionally used to track adverse effects.

2. The IPBES Framework: Used by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services to track nature’s positive contributions.

Scientific Significance: The innovation here is repurposing DPSEEA. Historically used since the 1990s to trace how Industry leads to Pollution and then Disease, the authors flip the model to trace how Restoration leads to Ecosystem Function and then Wellbeing. This addresses a known gap in literature regarding the lack of standardized "positive health indicators."

The Ecosystems Cascades Model: A Case Study in Heat Stress

The authors present the "Ecosystems Cascades Model" to trace the pathway from ecological intervention to human health. They illustrate this with Agroforestry (planting trees alongside crops) in East Africa.

• The Pathway: Native trees (Action) --> increased shade and evapotranspiration (Function) --> reduced solar radiation and ambient temperature (Exposure Change)

  --> reduced heat strain (Health Effect).

• Broader Literature Connection: This model is strongly supported by Occupational Environmental Medicine.

  
  

  • Physiological Evidence: Research from the International Labour Organization (ILO) and studies in Frontiers in Forests and Global Change confirm that agroforestry microclimates can be 2–4°C cooler than open fields.

  
  

  • Clinical Outcomes: The paper links this cooling directly to reduced Chronic Kidney Disease of Non-traditional Origin (CKDnt). External studies validate that heat stress is a primary driver of kidney injury among tropical agricultural workers, confirming that the ecological intervention acts as a preventative medical intervention.

Biodiversity and Immune Regulation

The paper cites evidence that "biodiversity interventions improve children's immune regulation."

• Broader Literature Connection: This refers to the Biodiversity Hypothesis (an extension of the "Old Friends" hypothesis), pioneered by researchers like Ilkka Hanski.

• Key Evidence: The paper references a landmark study (Roslund et al., 2020) where daycare yards were covered in forest-floor vegetation. The result was a rapid alteration in the children’s gut microbiome and improved immune markers. This serves as a "proof of concept" that soil biodiversity is not just an ecological metric, but a direct determinant of human immunological health.

  
  

Path Forward: Data and Governance

To operationalize these findings, the authors call for:

• Shared Metrics: Developing indicators that measure the "quantity of ecosystem quality" needed to reduce specific health risks.

• Data Integration: They cite the collaboration between the Global Biodiversity Information Facility (GBIF) and the WHO as a model for linking vector-borne disease data with biodiversity data.

• Strategic Funding: Utilizing mechanism like the Green Climate Fund to support transdisciplinary projects that would otherwise fall between the cracks of "health funding" and "environment funding."

Summary

The paper by Murage, P., et al. (2025) moves beyond simply stating that "nature is good for you" by providing a mechanistic framework (The Ecosystems Cascades Model) that aligns with hard data from occupational medicine and immunology. It argues that protecting ecosystems is not just conservation—it is a preventative public health strategy.

References:

1. Murage, P., et al. (2025). Safeguarding natural ecosystems can protect population health: advancing approaches to bridge the health–ecology divide. The Lancet Planetary Health, 9, 101377.

2. Roslund, M. I., et al. (2020). Biodiversity intervention enhances immune regulation and health-associated commensal microbiota among daycare children. Science Advances, 6(42), eaba2578.

3. Dobhal, S., et al. (2024). Global assessment of production benefits and risk reduction in agroforestry during extreme weather events under climate change scenarios. Frontiers in Forests and Global Change.

4. Johnson, R. J., et al. (2020). Fructose metabolism as a common evolutionary pathway of survival associated with climate change, food shortage and droughts. Journal of Internal Medicine, 287(3), 252–262.

5. Shimabukuro, P., Groom, Q., & Fouque, F. (2024). Bridging Biodiversity and Health: The Global Biodiversity Information Facility's initiative on open data on vectors of human diseases. GigaByte, 2024, gigabyte117.