Exposure to very high temperatures would accelerate the aging of people over 55, according to a new study.
- The inhabitants of the districts which are exposed to more days of high heat, have a faster aging than the others.
- However, the first effects on cellular age can be observed in 7 days.
- Researchers encourage officials of town planning “to take into account heat mitigation measures and characteristics adapted to the elderly when they modernize the infrastructure of cities”.
If you have exceeded fifty, beware of heat waves. A new study by University of Southern California reveals that the aging of the elderly is accelerated during increased exposure to high temperatures.
The results were detailed in the journal Science AdvancesFebruary 26, 2025.
High temperatures cause epigenetic changes
To better understand the impact of extreme health on health, the researchers followed more than 3,600 participants aged 56 and over in all the United States.
Blood samples have been taken from volunteers at different times during the six years of research. They were then analyzed to detect epigenetic changes, that is to say changes in gene activity. Thanks to this data and mathematical tools, the team then estimated the biological age of the participants. They then compared it with the history of the heat index of their place of residence and the number of days when temperatures were high during the study.
The analysis revealed a significant correlation between the districts where there are more days of extreme heat (between 32.2 and 39.4 degrees) and a greater increase in biological age in residents.
“Participants living in regions where days of heat, defined as extreme or higher level (≥ 32 degrees), occur half of the year, as in Phoenix (in Arizona), have known up to 14 months of additional biological aging compared to those living in regions where there is less than 10 days of heat per year”specifies the co-author Eunyoung Choi in a press release.
Heat peak: even a short exposure can speed up aging
However, a few days a year with a thermometer over 30 degrees seem sufficient to speed up aging. The study also observed an association after short (7 days) and medium (30 to 60 days) periods. For researchers, this suggests that heat -related epigenetic changes would be likely to occur relatively quickly and that some of them could accumulate over time.
After the discovery of this association, the team now wants to identify all the factors that could make a person more vulnerable to biological aging linked to heat.
In the meantime, researchers encourage political decision -makers, architects and urban planners “To take into account heat mitigation measures and the characteristics adapted to the elderly when they modernize the infrastructure of cities, by placing sidewalks and by building bus stops thinking in the shade, planting more trees and increasing urban green spaces”.
“If global warming continues everywhere, the population is aging and these people are vulnerable, we must then adopt much smarter attenuation strategies”explains the main author Jennifer Ailshire.
