As the world remains dependent on fossil fuels and falls short of its climate goals, a new report has issued a grave warning: climate inaction is now endangering global health. The 2025 Lancet Countdown on Health and Climate Change, released in partnership with the World Health Organization (WHO), highlights that rising temperatures, extreme weather, and pollution are already claiming millions of lives. Twelve out of twenty key health indicators have reached record levels, underscoring how environmental neglect is straining health systems, reducing productivity, and weakening economies. The findings reinforce that every fraction of a degree of warming matters and that urgent climate action is essential not just to protect the planet, but to safeguard human life worldwide.
Climate change is harming health and threatening global safety: Report
According to the report, 12 of the 20 indicators tracking climate-related health threats have reached record levels. These include extreme heat exposure, food insecurity, and rising air pollution, all of which are undermining health systems and weakening global economies.Dr Jeremy Farrar, WHO’s Assistant Director-General for Health Promotion, warned that the climate emergency is no longer a future risk but a present-day health catastrophe. “Every fraction of a degree of warming costs lives and livelihoods,” he said, stressing that climate action is also humanity’s greatest health opportunity. Cleaner energy, sustainable diets, and resilient healthcare systems can together save millions of lives and secure a healthier planet for generations to come.
Rising heat and extreme weather are claiming more lives
The Lancet Countdown 2025 report paints a troubling picture of how heat and extreme weather are already driving up death rates. The rate of heat-related mortality has surged by 23% since the 1990s, with an average of 546,000 people dying from heat exposure every year.In 2024, the average person endured 16 days of extreme heat that would not have occurred without climate change. Vulnerable groups, particularly infants and older adults, faced up to 20 heatwave days per person.
Heatwaves, droughts and fossil fuels are deepening the global crisis
Droughts and wildfires are increasingly linked to worsening food insecurity and malnutrition. In 2023, an additional 124 million people faced moderate or severe food insecurity due to prolonged droughts and heatwaves. This growing instability in food production threatens both physical health and economic security, particularly in developing nations dependent on agriculture.Beyond the devastating health effects, the economic consequences of rising temperatures are staggering. Heat exposure cost the world 640 billion potential labour hours in 2024, equating to productivity losses worth over US$ 1.09 trillion. Among older adults, the costs linked to heat-related deaths reached US$ 261 billion.At the same time, global fossil fuel subsidies remain alarmingly high. Governments collectively spent nearly US$ 956 billion on net fossil fuel subsidies in 2023 more than triple the annual amount pledged to climate-vulnerable nations. Shockingly, fifteen countries spent more subsidising fossil fuels than they did on their entire national health budgets.
Reverse the deadly health risks with positive climate action
The report also highlights encouraging signs that meaningful climate action can reverse these deadly trends. Between 2010 and 2022, reduced coal pollution prevented an estimated 160,000 premature deaths each year. Renewable energy sources reached a record 12% of global electricity generation, creating 16 million new jobs across the world.In 2024, two-thirds of medical students received education on the intersection of climate and health, marking a major step towards preparing the next generation of health professionals to address climate-related challenges.Dr Marina Romanello, Executive Director of the Lancet Countdown at University College London, emphasised that solutions already exist. “Communities worldwide are showing that progress is possible,” she said. “Phasing out fossil fuels, adopting renewable energy, and embracing sustainable diets could save over ten million lives each year.”
Communities step up to protect health and the planet
While some governments have slowed down their commitments, cities, communities, and the health sector are stepping up. Nearly all participating cities (834 out of 858) have already conducted or are planning climate risk assessments. The transition to clean energy is delivering tangible benefits, including cleaner air, better jobs, and healthier urban environments.The health sector itself is setting a strong example. Between 2021 and 2022, health-related greenhouse gas emissions fell by 16% globally, even as care quality improved. WHO data show that 58% of member states have completed a Health Vulnerability and Adaptation Assessment, while 60% have finalised a Health National Adaptation Plan both crucial tools for preparing health systems for climate-related risks. As the world prepares for COP30 in Belém, Brazil, the Lancet Countdown report provides critical evidence for accelerating health-centred climate action. The WHO plans to build on this momentum through its upcoming COP30 Special Report on Climate Change and Health, which will outline policies and investments needed to safeguard public health and promote equity.The Belém Action Plan, expected to be the key outcome of COP30, aims to embed health protection within all major climate strategies. Experts believe that recognising human health as the driving force behind climate policies could finally unite governments, businesses, and communities in tackling the crisis with the urgency it demands.Also Read | Is it safe to boil water in a microwave? Scientists reveal the hidden dangers behind this everyday habit
