The idea that human health exists separately from the environment is becoming outdated. From worsening air quality in rapidly growing cities to shifting disease patterns linked to climate change, the evidence is clear: human well-being is closely tied to the state of the natural world.
This is the foundation of planetary health, an emerging field that reframes health not just as a medical issue but as complex interactions between human systems and the Earth’s ecosystems.
On the Global Health Matters podcast, Garry Aslanyan hosted Dr. Catherine Kyobutungi and Dr. Ricardo Baptista Leite to unpack a concept that is gaining global significance.
Although still unfamiliar to many, Dr. Kyobutungi explains that planetary health emerged over a decade ago through the Lancet Planetary Health Commission. The Lancet publishes a dedicated journal on the subject.
Ricardo Baptista Leite notes that it is no longer feasible to understand human and animal health in isolation from the environments in which they exist. The air people breathe, the food they consume, and the conditions in which they live are not external factors—they are central determinants of health.
“When I have a patient in front of me, I am analyzing their clinical status, which actually only impacts 10% of their health status… 60% of each individual’s health is influenced by what we call exogenous factors.”
Kyobutungi adds that the issue extends beyond healthcare into the broader development model. While progress has been measured by visible infrastructure—highways, skyscrapers, and rapid urban expansion, the model ignores environmental costs that ultimately undermine human well-being.
“The world does not have unlimited resources…at some point it becomes clear that it’s not sustainable to pretend that the planet is going to accommodate everything we do,” she says, highlighting the contradiction.
She also argues that the world should rethink what development means. “We need a new paradigm that says development is actually when you have clean air, you have clean water, maybe you have green areas, not tall buildings and not super highways and not like traffic jams. That’s not the sign of development.”
Around the world, this tension is already evident. Dr. Kyobutungi points out that agricultural land is increasingly being converted into real estate, reducing local food production while increasing dependence on external supply chains. Urban growth, once seen as a sign of progress, is now raising serious questions about long-term sustainability.
“We want houses, but we’re not thinking about the food-producing land that we are converting into concrete,” she says.
Why change has been slow
Despite mounting evidence, global systems have been slow to adopt planetary health approaches, even though they offer significant long-term benefits. According to Richardo Baptista, one key reason is political: preventative action is difficult to prioritise because its success is often invisible.
“If they are very successful, no one will notice,” he explains. This creates a paradox—policies that prevent crises are often the least politically rewarded.
There is also a communication gap. Scientists generate vast amounts of data but often struggle to translate it into compelling narratives about risk and consequence. “We don’t focus enough on discussing what will happen if politicians don’t act,” he argues.
Without a clear understanding of the cost of inaction on planetary health, decision-makers are less likely to commit to long-term sustainability investments.
Local reality of global challenges
While planetary health is a global framework, its impacts are felt most acutely at the local level. Cities and communities are where environmental decisions translate into lived realities–whether through flooding, air pollution, or access to green spaces.
Richardo Baptista emphasises the importance of measurable outcomes over symbolic achievements:
“It doesn’t matter how you’re being praised. It matters what the outcomes are, how you’re measuring them, and the actions you take.”
This underscores the need for stronger local data systems and accountability mechanisms. Without them, global goals risk remaining abstract and disconnected from everyday life.
New risks in a changing world
Dr. Kyobutungi also points out that even as the world embraces new technologies, the planetary health lens raises important concerns. The rapid expansion of artificial intelligence and digital infrastructure, for instance, carries significant environmental costs.
“We want AI, but we want responsible AI… if we pursue it at all costs, that’s where the problem lies,” she says.
Data centres consume vast amounts of energy and water, potentially exacerbating the very challenges planetary health seeks to address. This highlights the need for innovation that is not only advanced, but also sustainable.
A shift in mindset
Planetary health demands a fundamental shift in how we think about progress and responsibility. As Kyobutungi notes, sustainable development requires empowering communities, reducing dependency, and enabling societies to take ownership of their development paths.
“At some point we have to reach that point in our consciousness that we need certain things but it’s not at the expense of the physical systems in which we exist as a species,” she said.
IMAGE CREDIT: AI