Many people dream of retiring to warmer climates, seeking the comfort of sunny skies and milder temperatures. However, there’s an unexpected twist to the plot: living in hotter environments may accelerate the aging process.
Studies have shown that exposure to extreme heat can have adverse effects on health. In the latest study published in the journal Science Advances, the researchers explored how environmental heat affects biological aging.
The study involved over 3,600 participants from the Health and Retirement Study (HRS), all aged 56 and older, from across the U.S. Over a six-year period, researchers collected blood samples from the participants at various points to analyze epigenetic changes. These changes occur when certain genes are turned ‘on’ or ‘off’ through a process called DNA methylation.
Using mathematical tools known as epigenetic clocks, researchers studied methylation patterns and estimated the participants’ biological ages at different times during the study. They then compared these changes in biological age with the heat index history and number of heat days recorded by the National Weather Service from 2010 to 2016 based on each participant’s location.
Since the study used the heat index, it took into account the combined effects of heat and humidity, rather than just air temperature, to analyze its impact. The researchers highlighted that this is especially important for older adults, as they do not sweat as effectively.
“People in neighborhoods that experience more days of high heat show greater biological aging on average than residents of cooler regions,” said Jennifer Ailshire, senior author of the study in a news release.
For example, just seven days of heat could result in aging about 1 year faster. Longer exposure to extreme heat, such as a year, had an even stronger effect, making aging faster by nearly 2.5 years.
“Participants living in areas where heat days, as defined as Extreme Caution or higher levels (≥90°F), occur half the year, such as Phoenix, Arizona, experienced up to 14 months of additional biological aging compared to those living in areas with fewer than 10 heat days per year,” co-author of the study, Eunyoung Choi said.
“Even after controlling for several factors, we found this association. Just because you live in an area with more heat days, you’re aging faster biologically,” Choi added.
