Climate Inaction Kills Millions Annually—New Lancet-WHO Report Warns

In a joint statement issued on Wednesday, the organisations called for urgent recognition of health as the most powerful driver of climate action.

The warning comes with the release of the 2025 Lancet Countdown on Health and Climate Change, produced in collaboration with WHO. The report found that 12 of 20 key indicators tracking health threats have reached record levels, highlighting how overreliance on fossil fuels and failure to adapt to a warming planet are taking a devastating toll on human health.

"The climate crisis is a health crisis. Every fraction of a degree of warming costs lives and livelihoods," said Dr Jeremy Farrar, Assistant Director-General for Health Promotion and Disease Prevention and Care at WHO. "Climate inaction is killing people now in all countries. However, climate action is also the greatest health opportunity of our time. Cleaner air, healthier diets, and resilient health systems can save millions of lives now and protect current and future generations," he added.

The report revealed that heat-related mortality has increased by 23 per cent since the 1990s, with an estimated 546,000 deaths per year. In 2024 alone, the average person was exposed to 16 days of dangerous heat that would not have occurred without climate change. Extreme weather events like droughts and heatwaves contributed to food insecurity for an additional 124 million people in 2023.

The economic cost has also been staggering. Heat exposure led to the loss of 640 billion potential labour hours in 2024, equivalent to USD 1.09 trillion in productivity losses. The financial cost of heat-related deaths among older adults reached USD 261 billion.

The report also criticised governments for continuing to pour vast sums into fossil fuel subsidies, which totalled USD 956 billion in 2023--over three times the amount pledged to support climate-vulnerable countries. Fifteen nations reportedly spent more on fossil fuel subsidies than on their national health budgets.

Despite the bleak outlook, the report highlighted the positive health benefits of decisive climate action. Between 2010 and 2022, reductions in coal-based air pollution prevented an estimated 160,000 premature deaths annually. Renewable energy generation reached 12 per cent of global electricity in 2024, creating around 16 million jobs worldwide.

Dr Marina Romanello, Executive Director of the Lancet Countdown at University College London, emphasised that the tools to prevent further catastrophe already exist.

"We already have the solutions at hand to avoid a climate catastrophe - and communities and local governments around the world are proving that progress is possible. Rapidly phasing out fossil fuels in favour of clean renewable energy and efficient energy use remains the most powerful lever to slow climate change and protect lives," she said.

The report also praised cities, communities, and the health sector for leading the charge despite slowing national commitments. Nearly all reporting cities--834 out of 858--have completed or plan to complete climate risk assessments. The health sector itself has reduced its greenhouse gas emissions by 16 per cent globally between 2021 and 2022 while maintaining care quality.

According to WHO, 58 per cent of its Member States have now completed health vulnerability and adaptation assessments, while 60 per cent have finalised national health adaptation plans.

As the world prepares for COP30 in Belem, Brazil, the report calls for placing health at the centre of global climate action. WHO announced that it will release a COP30 Special Report on Climate Change and Health, outlining the policies and investments needed to safeguard health and equity as part of the forthcoming Belem Action Plan.

Now in its ninth year, the Lancet Countdown on Health and Climate Change is a collaboration between WHO, University College London, and 71 academic and UN institutions, with core support from Wellcome. It remains the most comprehensive annual assessment of the health impacts of climate change and the benefits of urgent, coordinated climate action.

- ANI