DEADLY HEAT: It can age you as fast as smoking or alcohol

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A group of scientists from Taiwan studied the human body’s response to climate change. According to their research, abnormal heat can significantly accelerate the aging process of our bodies and also make us more vulnerable to diseases.

MORE HEAT — MORE PROBLEMS

n the experiment, the results of which were published in the journal Nature Climate Change, 24,922 people took part. By studying the impact of rising ambient temperatures on people, Taiwanese scientists found that abnormal heat has an invisible yet destructive effect. Moreover, it has a cumulative impact, gradually accelerating the biological clock and increasing a person’s biological age, roughly to the same extent as regular smoking or alcohol consumption. The research showed that the more extreme heatwaves a person experienced, the faster their organs aged.

HEAT LEADS TO ORGAN OVERLOAD

Exposure to extreme heat, especially over a long period of time, leads to overstrain of the internal organs. They begin to work in emergency mode, which, in turn, can result in death. In general, scientists had previously understood that heatwaves can create problems for the normal functioning of the body. However, the discovery that they can systematically age it came as a surprise for the first time.

The scientific community believes this effect is yet another alarming signal of how vulnerable we all are to the adverse impact of climate change on our health. And if people do not want to age prematurely, they have one more reason to radically reduce greenhouse gas emissions into Earth’s atmosphere.

ANOTHER RISK FACTOR

Age is not simply the result of the passage of time. The process of aging, with all the accompanying physiological changes, is triggered by a number of interconnected factors. Among them are environmental and social stress, genetics, and medical interventions. All of these increase the risk of cardiovascular diseases, cancer, diabetes, and dementia. It has turned out that abnormal heat also holds a prominent place on the list of risk factors.

To study its long-term impact on aging processes, Taiwanese scientists analyzed medical examination data collected between 2008 and 2022. During this period, about 30 temperature anomalies were recorded in the country — periods when the temperature rose sharply for several consecutive days.

HEAT ACCELERATES THE BIOLOGICAL CLOCK

To calculate biological age, the researchers used the results of a series of medical tests, including assessments of blood pressure, inflammatory processes, and liver, lung, and kidney function. The scientists then compared biological age with the cumulative temperature exposure in the participants’ places of residence during the two years preceding their medical visit. It turned out that the more extreme heat events people experienced, the faster they aged. Every additional 1.3 °C in the environment where a participant lived added approximately 0.023–0.031 years to their biological clock.

WHO AGES THE MOST FROM HEAT

At first glance, this number may seem small. However, the insidiousness of heat exposure lies in the fact that it does not show its effects immediately, but over time. Moreover, its consequences can be especially harmful for certain population groups. For example, those engaged in physical labor are the most vulnerable. For rural residents, heat creates far more problems than for city dwellers. This is likely because these people have limited access to air conditioning.

WE CAN ADAPT TO TEMPERATURE ANOMALIES!

During the study, scientists made another unexpected discovery that gave them a measure of optimism. While studying the link between abnormal heat and aging, they analyzed data spanning 15 years. It turned out that during this period, the negative impact of abnormally high temperatures on the body gradually decreased. In other words, people somehow adapted to them.

Unfortunately, the scientists have not yet been able to determine the exact causes and mechanisms of this adaptation. They only suggested that the improvement in indicators is connected with the fact that every year, the population gains greater access to cooling technologies. On the other hand, in developed countries, there is no shortage of air conditioning, yet abnormal heat ages their populations even faster.

ALL COUNTRIES SUFFER FROM HEAT

In 2023, German colleagues of the Taiwanese scientists conducted a similar study based on data collected in Germany. It showed that higher air temperatures are associated with a greater number of epigenetic markers of aging. In the United States, researchers analyzed DNA markers of more than 3,600 elderly people. The American findings were also discouraging: extreme heat leads to premature aging. However, the most significant concern about prolonged heat exposure is its potential to have lifelong consequences for human health.

HEATWAVES ARE BECOMING MORE FREQUENT

Climate change increases the likelihood of negative health consequences from heat, as episodes of extreme temperatures are becoming more frequent. Since 2010, the United States has observed about six heatwaves each year. In the 1960s, there were only two. Each year, heatwaves are becoming increasingly deadly. In 2022, when temperatures in Pakistan and India reached 50 °C, the number of heat-related deaths rose sharply. Scientists state that heatwaves have long ceased to be merely an individual risk factor. Their growing frequency is becoming a global problem for all nations on the planet, regardless of their geographic location or level of economic development.

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