Does keeping cool keep you young? How climate change affects aging.

At first, climate change and aging may seem like unrelated challenges. Climate change is the reshaping of our environment that results in extreme weather events, like heat waves. Aging challenges our society by burdening our healthcare and social support systems. Both seem daunting on their own: the world keeps heating up, and the proportion of the world population that is aging is constantly expanding. But how do they impact each other? 

Scientists from the University of Hong Kong have recently shown that heat waves can cause an increase in biological age – how old your body appears based on a set of biomarkers. They tracked nearly 25,000 Taiwanese people from 2008-2022, determined their exposure to heat waves, and recorded their habits, such as smoking, drinking, and exercise. By comparing these habits to biomarkers in blood samples, scientists determined the difference between their biological age and traditional chronological age – time since birth. Here, they found that exposure to heat waves accelerated aging to a similar extent as smoking and drinking. The greater the exposure to extreme heat, the greater their age accelerated. Interestingly, communities that added more AC units over time reduced the rate of age acceleration in their inhabitants. 

While it may be catchy to call heat waves as bad as smoking or drinking, the effects measured on all three in this study were small. This study focused on a large group over a long period of time. This way, small effects can add up to a huge societal impact – increased disease burden, healthcare costs, and mortality. You may not notice one person getting one percent older because of heat waves, but this study has shown that the effect heat waves have on our collective biological age is a critical public health issue. 

This study was led by Siyi Chen, a researcher at the Department of Urban Planning and Design, Faculty of Architecture in the University of Hong Kong, Hong Kong, China

Managing Correspondent: Samuel Lapp

Press Article: Repeated Heat Waves Can Age You as Much as Smoking or Drinking (Scientific American)

Original Journal Article: Long-term impacts of heatwaves on accelerated ageing (Nature Climate Change) 

Image Credit: Pixabay