Call for urgent global research into the mental health impacts of extreme heat 

On World Mental Health Day (Thursday 10 October), world-leading scientists warn there is an urgent need for research examining the impact of climate change and extreme heat on mental health.

The year 2023 was the hottest year on record according to the EU’s Copernicus Climate Change Service and the streak has continued in 2024.  

The Physiological Society, Wellcome and the University of Portsmouth are calling for joined-up cross disciplinary efforts to improve our understanding of physiological mechanisms linking extreme heat and mental health, and implement low-cost cooling interventions, with a focus on countries disproportionately affected by heat.

Professor Mike Tipton MBE, Trustee of The Physiological Society and co-founder of the University of Portsmouth’s Extreme Environments Lab (EEL), said: “While the correlation between heat and mental health problems is clear, the physiological mechanisms driving these worsened outcomes are under-researched and poorly understood. 

“Physiological interventions are an essential part of the solutions that will need to be developed. For example, understanding how heat affects our sleep and the long-term implications of the body’s response, would improve not only physiological interventions but also address some of the psychological and social drivers of poorer outcomes.” 

Last year,  The Physiological Society, in partnership with the Faculty of Public Health, called for Parliament to protect people from the effects of climate change. The report called for the development of a heat resilience strategy focused on improving the understanding of how heat impacts our bodies, especially vulnerable groups, such as those living with mental health conditions.  

In February this year, The Physiological Society and Wellcome  held a joint workshop, to explore the link between extreme heat and mental health. It brought together 80 experts from over 16 countries around the world and a variety of academic disciplines, including physiologists, epidemiologists, climate change experts, mental health practitioners, people with lived experience and pharmacologists.   

Madeleine Thomson, Head of Climate Impacts and Adaptation at Wellcome, said: “There is an urgent need to improve our understanding of how the body responds to extreme heat and the link with poorer mental health outcomes. Only 5% of scientific articles on health impacts of climate change in Europe focus on mental health. We urgently need more and better research, bringing together different disciplines from a variety of countries." 

Wellcome will be launching a new funding call looking at the mental health impacts of climate change in the first week of October. 

Other recommendations from the workshop include improving the use and integration of existing mental health and weather and climate data, ensuring a focus on mental health problems associated with extreme heat in low- and middle-income countries (LMICs) and implementing simple, cheap and sustainable cooling interventions and evaluate their impacts on mental health. 

"Affordable, low-carbon solutions like using ceiling fans to stay cool should be more widely encouraged, even though they're not usually mentioned in government advice", explained Professor Tipton.  

"We should try these out in trials or alongside existing research into health and climate to see how they affect mental health since there is little evidence so to demonstrate their value in this area."