For health systems, sustainability is survival

Healthcare accounts for about 4.6% of global net greenhouse gas emissions, making it the world’s fifth-largest emitter if it were a country. To keep protecting patients through intensifying heatwaves, floods, and wildfires, health systems must become low-carbon, climate-resilient, and resource-efficient within this decade, says Mark Wilson, Executive Director of Healthcare Without Harm Europe

Healthcare exists to protect and restore health. Yet its systems, built to heal, are fuelling the environmental crises that increasingly threaten human health – and are buckling under the climate impacts they are helping to create.

In June 2026, in Europe, that contradiction turned even more deadly. The record-breaking continental heatwave pushed temperatures towards 42°C. France triggered its highest level of healthcare mobilisation, with hospitals postponing non-urgent operations, recalling staff and clearing beds for a surge of admissions. Most of those admitted were over 75. Heat-related deaths in Europe have risen by 30% over the past two decades, and preliminary estimates point to at least 14,000 excess deaths across Western Europe during the record-breaking heatwave of June 2026 alone. But every region around the world faces the same reckoning: increased heatwaves, floods, typhoons and wildfires due to climate change, worsening human health, driving up demand for medical services, disrupting care, and damaging both health infrastructure and critical systems. These pressures will only intensify.

The task for the healthcare sector over the next decade is stark: keep protecting lives in the face of growing health challenges caused by climate extremes, while cutting its own carbon emissions that drive them. If it were a country, the health sector would be the world’s fifth-largest emitter (Health Care Without Harm, 2019). It can no longer treat sustainability as separate from patient care. Low-carbon, climate-resilient healthcare is now essential for delivering improved care to all – to keep services running, protect healthcare workers and safeguard public health.

Isolated initiatives will not be enough. Across Europe, members of Health Care Without Harm’s Global Green and Healthy Hospitals network are already proving what works. In Spain, Sant Pau’s Green Breath project cut the climate impact of inhalers across 40 hospitals. London’s Great Ormond Street Hospital helps children switch from intravenous and liquid medicines to low-carbon tablets. NHS Scotland’s Green Anaesthesia programme slashed emissions from medical gases. The challenge now is to massively scale up these and other initiatives, and integrate them into the core of how health systems are planned, funded and run.

That shift rests on three connected priorities.

How can health systems become climate-resilient?

For too long, cutting the healthcare sector’s carbon emissions whilst preparing for and recovering from the impact of climate-related shocks has been treated as separate agendas. They are inseparable. Lower emissions mean little if a hospital cannot run safely through a flood or a heatwave. But adaptation is an uphill battle if healthcare keeps contributing to the crisis at its current rate. The strain is already here. Healthcare professionals have told us that dangerous heat on the wards during recent heatwaves was unbearable to work in and contributed to errors in patient care.

Providers need practical tools to measure emissions, assess climate risks, and apply proven solutions across borders. Health Care Without Harm Europe is providing them with standardised methods and guides on decarbonising and adapting to climate change, so organisations can accelerate progress rather than reinvent the wheel.

How to accelerate the shift to circular healthcare

Supply chains – pharmaceuticals, devices, food, logistics and procurement – cause about 71% of healthcare’s environmental footprint (Health Care Without Harm). Yet circularity is about resilience as much as it is about waste: Recent supply-chain shocks caused by the war in the Middle East, COVID-19, and extreme weather have all exposed how fragile this system built on constant consumption and disposal really is.

The future of healthcare means moving beyond ‘single-use by default’ supplies and products to healthier, ‘circular’ practices: reusing where clinically safe, avoiding plastics and hazardous chemicals when not necessary, and building sturdier supply chains.

Better environmental performance and improved patient safety can reinforce one another rather than be seen as competing priorities. Procurement is one of the most powerful – and most underused – levers for change. What health systems buy shapes entire markets and influences how medicines are made, devices are designed, and what food systems emerge. Governments and European institutions must set the rules and incentives that let sustainable markets grow. Until they do, sustainability in the healthcare sector will remain optional, and progress will be fragmented.

Why the climate response must cross borders

No country can transform healthcare alone. Climate change ignores borders, and so must the response. National systems are beginning to act. In 2025, Belgium and Ireland published landmark national health emissions baselines and decarbonisation roadmaps using HCWH Europe’s proven Operation Zero methodology, turning climate commitments into practical action. We hope more countries will adopt this methodology to help them plan for, implement and deliver net-zero healthcare systems.

The next decade decides

The coming decade will determine whether healthcare stays reactive – adding to the crisis and absorbing its worst blows – or becomes one of society’s strongest engines of resilience, proving every sector can make this transition.

Treating the symptoms of the climate crisis will not be enough. Healthcare must address the root causes by becoming low-carbon, circular and climate-resilient.

Lives depend on it.