Conservation Medicine 7

Planetary Health: Definition, Principles, and Practices for a World in Transition

In a time of cascading global crises—climate instability, pandemics, biodiversity collapse, and widening health disparities—the very foundations of the public’s health and their commons are being redefined. The old models, built largely on the biomedical-industrial complex, can no longer hold. A more expansive and integrative framework has emerged: Planetary Health.

Planetary Health is more than an emerging discipline—it represents a fundamental paradigm shift. It asks civil society to understand health as inseparable from how we steward Earth’s ecosystems and safeguard the life-supporting services they provide. At its core, Planetary Health is a call to protect the well-being of all living beings and to preserve the ecological foundations upon which human and planetary flourishing depend.

Defining Planetary Health

The concept of Planetary Health was formally introduced in The Lancet-Rockefeller Foundation Commission Report in 2015. It defines Planetary Health as:

“The health of human civilization and the state of the natural systems on which it depends.”

This definition insists on a systems-level understanding of health, recognizing that human flourishing is inseparable from the health of our environment—from climate, air, and water, to biodiversity, soil quality, and global food systems.

Planetary Health builds on, and expands, the One Health and EcoHealth approaches. While those frameworks emphasize interspecies and environmental connections, Planetary Health uniquely centers the socio-political, economic, and ethical drivers that shape those interactions on a planetary scale.

Core Principles of Planetary Health

Planetary Health is grounded in a set of unifying principles that are both visionary and practical:

1. Interdependence

Human health cannot be disentangled from the health of natural ecosystems. Policies and practices that degrade the environment ultimately degrade our health, whether through climate-related illnesses, water insecurity, or exposure to pollutants.

2. Equity and Justice

The planetary health crisis disproportionately affects the most vulnerable—those least responsible for environmental degradation. Climate justice, health equity, and intergenerational responsibility are foundational concerns.

3. Sustainability

Health gains must not come at the expense of future generations. Economic development, urbanization, and technological advancement must be aligned with ecosystem resilience and regenerative systems.

4. Systems Thinking

Planetary Health rejects linear, reductionist approaches. It embraces complex, interconnected systems and emphasizes feedback loops, trade-offs, and unintended consequences in principle, policy, and practice.

5. Stewardship

Planetary Health calls for a cultural and ethical transformation—from extraction to stewardship, from domination to reciprocity. It invites humility in the face of nature’s complexity and reverence for the biosphere.

Planetary Health in Practice

The movement is not just theoretical—it is transforming how we think, teach, research, and govern health systems globally. Here are a few examples of how Planetary Health principles are being applied:

🌱 In Healthcare

Hospitals and clinics are adopting climate-smart practices—reducing GHG emissions, managing waste sustainably, sourcing food locally, and educating patients about environmental determinants of health.

🌍 In Education

Universities are integrating Planetary Health across disciplines—preparing future physicians, nurses, policy leaders, and scientists to think ecologically and act systemically.

🧭 In Public Policy

Cities are redesigning infrastructure for resilience: expanding green spaces, transitioning to clean energy, and implementing nature-based solutions to reduce urban heat and improve air quality.

🐾 In Research

Interdisciplinary studies are examining how ecosystem collapse affects everything from mental health to nutrition. Evidence is growing on the co-benefits of environmental protection and disease prevention.

🫱🏽‍🫲🏼 In Global Collaboration

The Planetary Health Alliance and related networks are connecting thought leaders, institutions, and grassroots organizations to build a new field of action—one that prioritizes planetary boundaries and human dignity in equal measure.

The Urgency of Now

Planetary Health is not a distant aspiration—it is an emergency response to the Anthropocene. The health of the planet is declining faster than at any point in human history. The choices we make today—individually and collectively—will determine the kind of world we pass on to future generations.

But this is also a moment of profound possibility. We can reimagine health, not just as the absence of disease, but as the presence of thriving communities, resilient ecosystems, and just institutions.

A Personal Note

As a physician and advocate for transformative health systems, I find Planetary Health to be one of the most hopeful and necessary frameworks of our time. It reminds us that the body, the community, and the Earth are not separate stories. They are chapters in the same narrative.

If we are to heal, we must do so together—across disciplines, geographies, and generations.