by The souped, suffocating extreme heat that has burned parts of the northern hemisphere this summer demands hard tributes to our body. You can feel bad, woozy and dehydrated. It can have harmful health effects on several organs.
But there is another, less known influence of extreme heat: they age faster.
Longer exposure to rising temperatures can lead to a deterioration in our cells and tissues and accelerate biological aging according to new and growing research.
The chronological age refers to how long a person has lived, but age is measured how well our tissues and cells work. The difference between the two explains why the age of a person sometimes does not match his health and vitality.
An accelerated biological age is the “canaries in the coal mining” for the future risk of previous diseases such as cancer, dementia and diabetes and early death, said Jennifer Ailshire, professor of gerontology and sociology at the University of Southern California Leonard Davis, School of Gerontology.
Since climate change forces people to endure more and more serious and longer heat waves, scientists say that there is an urgency to better understand the way in which heat is slowly and tacitly undermine at cellular level.
How does the heat accelerate aging?
Our DNA is determined at birth; It is the blueprint for how the body works and cannot be changed.
The way in which the DNA is expressed – the way this blueprint is carried out – can be influenced by external factors that trigger chemical modifications, which are turned on or off genes such as a light switch.
External factors that influence these switches include behaviors such as smoking and lack of movement as well as environmental factors such as heat.
Heat burdens the body and lets it work harder when it tries to cool off what can damage cells. While a little heat stress can be good for the body, which increases resilience, longer exposure tax over longer periods of exposure taxes and long -term consequences.
A woman enjoys the sun when she tries to stay cool during a heat wave along the Brooklyn bridge. – Spencer Platt/Getty Images
Research on animals has pointed out strong associations between heat and acceleration of aging, but until recently there were very few studies that examined people.
Ailshire is one of the scientists who try to change that. In February, she and another researcher, Eunyoung Choi, published the first research on the population scale in this area.
They analyzed blood samples from a group of more than 3,600 people in the United States from the age of 56. They used tools that are referred to as “epigenetic watches” and that grasp the way in which the DNA is modified and provide an estimate of biological age. In the years before the blood samples were removed, they linked this to the daily climate data at the locations of the participants.
Her results published in February found people who experienced at least 140 extreme warmth days a year – as the heat index, a combination of temperature and humidity, over 90 degrees Fahrenheit – at the age of up to 14 months faster than those in places with less than 10 extreme heat a year.
This connection between heat and organic aging remained even taking individual factors such as training levels and income into account, although the study did not examine access to air conditioning or outside of outside times.
The strength of the association was also significant. The results showed that extreme warmth had the same influence on aging as smoking or strong alcohol consumption.
Your results are supported by other recent research results.
A 2023 study with more than 2,000 people in Germany showed that heat exposure was associated with an accelerated biological aging in the medium and long-term heat. The effects were particularly pronounced in women who can be more susceptible to warmth because they tend to sweat less, which means that it is more difficult for them to cool off. People with diabetes or obesity were also rather at risk, according to the study.
The effects can even begin before birth.
In a study of 2024, the accelerated biological aging was dealt with in children in Kenya who were exposed to the fetuses of drought. During pregnancy, their mothers suffered heat as well as dehydration and emotional stress.
These factors can cause stress at cellular level that has to be repaired, which means that less energy is available for other important functions, which may lead to accelerated aging, according to the study. Heat stress can also reduce blood flow to the uterus and placenta.
“So we see an impact on growth that includes lower birth weights and an overall more difficult beginnation of life – all of this can reflect at a faster biological aging,” said Bilinda Straight, study author and professor at the School of Environment, Geography and Sustainability at Western Michigan University.
What can people do?
Knowledge does not mean that everyone who lives in hot places experiences accelerated aging, said Ailshire. Every person has their own risk factors and there are ways to adapt.
Access to cooling and avoiding movement in the hottest parts of the day is important. Better nutrition, more movement (in the cool parts of the day) and medication can also help, she added. Scientists have found medicines such as metformin that were prescribed for diabetes, and the weight loss drug that Ozempic can slow down.
If people can change or find paths to adapt to their heat exposure levels, it may be possible to slow down or reverse the accelerated aging process, said Ailshire. “Because this is not permanent damage; it is an indicator of the potential for permanent damage. It does not necessarily mean that this damage has been done.”
Jessica Gomez and Lesli Rodriguez rest in Harrison Park in the Pilsen district in Chicago, when extreme heat and increasing summer temperatures met Chicago on July 23. – Audrey Richardson/Reuters
The study area is very new. “We are at the beginning of the understanding of this process, especially in humans,” Rongbin Xu, Research Fellow at the School of Public Health and Preventive Medicine at Monash University in Australia.
But if the places warm up and heat records are still being smashed, scientists will have a lot more data about the countless methods that affect our body – and who is most susceptible.
“If we cannot do anything about rising temperatures, we have to increase at least awareness and find strategies,” said Ailshire.
“There must be a way to get through it.”
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