Report of the
Lancet Countdown
The latest Lancet Countdown report warns that health impacts of climate change are worsening, with millions dying needlessly each year due to fossil fuel dependence, growing greenhouse gas emissions, and failure to adequately adapt.
As some countries and companies rollback on climate commitments, local and grassroots leadership is building momentum for a healthier future.
The report represents the work of 128 experts from 71 institutions, monitoring progress across 57 indicators – from heat-related deaths to bank lending to fossil fuels – providing the most comprehensive assessment yet of the links between climate change and health.
Key Messages
DELAYS IN CLIMATE CHANGE ACTION ARE INCREASINGLY COSTING LIVES AND LIVELIHOODS
Millions of people die needlessly each year due to fossil fuel dependence, growing greenhouse gas emissions, and failure to adequately adapt to climate change. Health risks and impacts of climate change are worse than ever before across 13 of 20 impact indicators.
BACKSLIDING ON CLIMATE CHANGE ACTION IS PUTTING PEOPLE IN HARM’S WAY
Fossil fuel investments are growing, adaptation finance remains insufficient, and energy-related emissions reached unprecedented levels. With adaptation becoming increasingly costly and challenging, reversal of climate commitments poses unprecedented threatens to human lives and wellbeing.
CLIMATE CHANGE ACTION OFFERS A LIFELINE
The life-saving impact of the limited action delivered is already being felt, and global momentum is building for further action. Countries leading the transition are already enjoying health and economic gains. Meanwhile local and grassroots leadership is building momentum for a healthier future, from the bottom up.
Explore key findings of this year’s report
The 2025 Report of the Lancet Countdown on Health and Climate Change: Climate change action offers a lifeline
HEALTH HAZARDS, EXPOSURES, AND IMPACTS
A changing climate has profound implications for human health, with more frequent heat waves and extreme weather events, changing patterns of infectious disease transmission, deterioration of food and water resources, impacts on socioeconomic conditions, and the exacerbation of existing health challenges around the world. Indicators in this section track the multiple ways in which climate change threatens human health and wellbeing.
1.1.5 Heat-related mortality
Failure to curb the warming effects of climate change has seen the rate of heat-related deaths surge 23% since the 1990s, to 546,000 a year.
1.2.1 Wildfires
The risk of wildfires is growing: 2024 saw a record-high 154,000 estimated deaths from wildfire smoke-derived small particulate matter air pollution (PM2.5)
1.3.1 Dengue
The global average transmission potential of dengue has risen by up to 49% since the 1950s.
ADAPTATION, PLANNING, AND RESILIENCE FOR HEALTH
With climate change increasingly threatening the health and wellbeing of populations in every country, actions to build resilience and adapt to climate change are urgently needed. This section tracks how communities, health systems, and governments are understanding the health risks of climate change, the strategies and resources they are deploying, and how adaptation and resilience measures are being implemented globally.
2.1.3 City climate change risk assessments
97% of cities reporting to the CDP (the world’s largest voluntary reporting system on climate change progress) in 2024 declared having completed, or intending to complete, climate change risk assessments
2.2.5 Climate and health education and training
The provision of climate change education to health professionals is building capacity for further progress. In 2024, 66% of 454 public health and 72% of 147 medical institutions worldwide provided climate and health education
2.2.4 Detection of, preparedness for, and response to, health emergencies
In 2024, 135 (69%) of 196 WHO member states reported having high-to-very-high implementation of health emergency management capacity, an increase of 4 countries with respect to 2023
MITIGATION ACTIONS AND HEALTH CO-BENEFITS
Reducing greenhouse gas emissions is essential to limit the health threats of climate change. Simultaneously, many of the interventions required to mitigate and adapt bring enormous benefits for human health and wellbeing in the form of cleaner air, healthier diets, and more liveable cities. Tackling climate change could be the greatest global health opportunity of the 21st century. Indicators in this section track the world’s efforts to mitigate climate change, and the effective and the health benefits of this response.
3.2 Air pollution and health co-benefits
Failure to transition to clean energy sources has led to an estimated 2.52 million deaths from fossil fuel derived outdoor air pollution, and an estimated 2.3 million deaths from dirty fuel-derived household air pollution in 2022
3.1.1 Energy systems and health
Clean energy access is deeply unequal, with Low HDI countries remaining especially reliant on dirty, harmful fuels Low HDI countries relied on renewables for just 3.5% of energy in 2022, compared to 12% in High HDI countries and 13% in Very High HDI countries
3.3.2 Diets and health co-benefits
Unhealthy diets contributed to 11.8 million largely preventable deaths a year between 2021-2022, including 1.9 million deaths from excessive red meat and dairy intake
ECONOMICS AND FINANCE
The health impacts of climate change have profound economic implications. This section tracks the economic costs of the health impacts of climate change and its drivers, as well as the extent to which the world’s economy and financial systems are enabling the transition to a health-promoting, zero-carbon economy.
4.3.2 Net value of fossil fuel subsidies and carbon prices
Our ongoing reliance on fossil fuels is forcing governments to pour staggering sums into subsidies, approaching an eye-watering US$1 trillion, to keep energy affordable to consumers.
4.2.2 Compatibility of fossil fuel company strategies with the Paris Agreement
By 2040, the planned production of the world’s largest 100 oil and gas companies would be almost three times (189% over) the amount that would be consistent with keeping global warming to 1.5°C, as of March 2025
4.3.3 Fossil fuel and green sector bank lending
Private bank fossil fuel lending reached a five-year high, surging 29% from 2023, to US$ 611 billion in 2024, exceeding green lending by 15%
PUBLIC AND POLITICAL ENGAGEMENT
Public and political engagement underpins the foundations of the world’s collective response to climate change, with reductions in global emissions at the speed required by the Paris Agreement depending on engagement from all sectors of society. This working group tracks key actors’ engagement with the links between health and climate change, including in the media, national governments, the corporate sector, and the broader public.The indicators in this section track the links between health and climate change in the media, national governments, the corporate sector, and the broader public.
5.4.1 Government engagement
Only 30% of countries mentioned health and climate change in their UN General Debate (UNGD) statement in 2024, down from 62% in 2021, despite the growing health harms felt around the world.
5.5 Corporate sector engagement
In 2024, only 51% of companies referred to the health dimensions of climate change in their UN Global Compact Reports, down from 63% in 2023.
5.1 Individual engagement with health and climate change
Individuals’ proactive engagement with health and climate change is increasing, with the average global Google search index increasing from 49.4 in 2023 to 59.9 in 2024, with the world’s most affected countries dominating the trend
Dr Githinji Gitahi, Group CEO of AMREF Health Africa
“This report once again provides strong evidence that the impact of climate change is being counted not just in degrees and carbon metric tonnes but in lives lost. The science reflects what communities across Africa experience daily – bearing the brunt of increasing heat-related deaths, rising infectious disease threats, and growing food and water insecurity. Health is the human face of climate change. “
Professor Charlotte Watts, Executive Director, Solutions at Wellcome
“This year’s Lancet Countdown is crystal clear about the global leadership we need: as the widespread impacts of climate change on lives and livelihoods become ever more visible, we know that urgent climate action will have significant benefits for health.
Progress is being held back by underfunding and wavering political will. This must change. At COP30, governments have a chance to accelerate health-centred climate action. Addressing the sources of climate change and investing in climate change adaptation will save people’s lives, strengthen economies, and cut emissions to secure a better future.”
Laura Clarke, CEO of ClientEarth
“We know what is needed to create a better future of clean air, healthy food and liveable cities. But too many governments and companies are turning away from that task, and even fuelling the climate crisis.
As attribution science, climate litigation and grassroots activism grow, accountability for climate impacts is no longer a question of if, but when.”
Summary for policymakers
Dive into the findings and their implications – a must-read for anyone shaping climate and health policy.
Country resources
Download country data sheets and policy briefs that explore the latest findings at a national level