The surprising link between heat waves and faster aging
New research from USC and Hong Kong links extreme heat to accelerated biological aging, adding days to the body’s internal clock.
You probably won’t be surprised to hear that smoking and drinking too much can cause your body to age more quickly. But heatwaves? That’s what scientists are now saying.
Record-breaking global heat
Although some still try to deny it, statistics show the world is getting hotter. NOAA and NASA confirmed 2024 as the hottest year ever recorded, while July 2025 ranked as the third-hottest month on record globally, behind only July 2024 and July 2023.
That spells bad news for many reasons, including personal health. While many of us live in areas where it gets uncomfortably hot at times, increasingly high temperatures can have a negative impact on overall well-being.
Heatwaves linked to faster aging
Recent studies from the University of Southern California and the University of Hong Kong reached similar conclusions: extreme heat and heatwaves can make people age prematurely.
According to the USC study, published earlier this year, 3,600 adults over age 56 living in hot areas across the United States showed greater biological aging than peers in cooler regions over a six-year period.
The University of Hong Kong study was even more extensive. Researchers analyzed medical data, including blood pressure, inflammation, and organ function, from 25,000 participants over 15 years. The results showed that for every additional 1.3ºC (34.3ºF) of exposure, approximately 0.023 to 0.031 years (8.4 to 11.3 days) were added to a person’s biological clock.
Long-term health risks
“While the number itself may look small, over time and across populations, this effect can have meaningful public-health implications,” Cui Guo, who led the University of Hong Kong study, told Nature.
“If heatwave exposure accumulates for several decades, the health impact will be much greater than we have reported,” Guo explained to The Guardian. “Heatwaves are also becoming more frequent and lasting longer, so the health impacts could be much greater in the future.”
Get your game on! Whether you’re into NFL touchdowns, NBA buzzer-beaters, world-class soccer goals, or MLB home runs, our app has it all.
Dive into live coverage, expert insights, breaking news, exclusive videos, and more – plus, stay updated on the latest in current affairs and entertainment. Download now for all-access coverage, right at your fingertips – anytime, anywhere.