Researchers calculated a daily heat index from 2010 to 2016, which incorporates both temperature and humidity to estimate the stress heat places on the body.

The heat index categorizes temperatures, with values of 90°F or higher indicating rising health risks, and those above 124°F classified as 'extreme danger'.

The authors of the study stressed the importance of public health policies to mitigate the risks associated with excessive heat, particularly as global temperatures continue to rise and populations age.

Notably, individuals living in areas with frequent heat days, such as Phoenix, Arizona, experienced up to 14 months of additional biological aging compared to those in cooler regions.

A recent study has revealed a significant link between increased heat days and accelerated epigenetic aging in older adults.

To assess the impact of outdoor heat on biological aging, researchers utilized epigenetic clocks to analyze data from over 3,500 adults aged 56 and older in the U.S.

Extreme heat has been associated with various health issues, notably cardiovascular diseases and increased mortality, with DNA methylation serving as a biological response to heat stress.

The findings suggest that short-term heat exposure has less impact on aging compared to long-term exposure, indicating cumulative health effects over time.

Different epigenetic clocks revealed varying associations between heat exposure and aging, with the PCPhenoAge clock showing significant effects across all levels of heat intensity and time frames.

The study concluded that heat affects all demographic subgroups similarly, although further research is necessary to investigate subgroup-specific responses to heat exposure.

Jennifer Ailshire, the senior author of the study, pointed out that older adults are particularly vulnerable to heat stress due to their reduced ability to sweat, especially in high-humidity environments.