Key points from article :
A new study published in Nature Climate Change warns that repeated exposure to heatwaves may speed up biological ageing, especially for people in physically demanding jobs and those without access to cooling. While past research focused on the immediate health risks of extreme heat in older adults, this study looked at long-term effects, analysing health data from 24,922 adults in Taiwan between 2008 and 2022. The researchers compared participants’ biological age—how well the body functions at the molecular and organ levels—to their actual age and found that frequent heatwave exposure was linked to accelerated ageing.
Biological age is considered a more accurate measure of health than chronological age, as it reflects the body’s resilience and risk of disease. The study revealed that people living in regions with more frequent heatwaves showed higher levels of “age acceleration,” meaning their bodies were biologically older than their birth age would suggest. Even though participants appeared to adapt somewhat to hotter conditions over the 15-year period, the harmful effects of repeated exposure did not disappear.
The research highlighted that manual labourers, rural communities, and populations with fewer air conditioners were the most vulnerable to this accelerated ageing effect. These groups not only experience higher physical stress but also often have fewer resources to protect themselves from extreme heat. The findings suggest that climate change is not just raising immediate health risks but also quietly shortening people’s healthy years of life.
The authors stress the need for policies that reduce environmental inequality and improve resilience against heatwaves, particularly in vulnerable populations. They also call for further research involving more diverse groups, and into how factors such as time spent outdoors, household conditions, and humidity interact with heat exposure. As humans age, the natural decline in temperature regulation makes older adults particularly at risk, underscoring the urgent need to adapt healthcare and infrastructure in a warming world.
