If we search the internet for the term overheating, we will find that we are talking about a phenomenon that affects the environment and humans on many levels. We will see, for example, that last April recorded monthly heat records on the ground and on the surface of the oceans, that in the seabeds of Australia the corals are “fading”, or that invasions by locusts may increase with dramatic consequences for crops and the food chain.
But evidence shows that overheating also threatens our physical and mental health, and even life expectancy appears to be significantly reduced by this invisible enemy. This was the conclusion reached by a team of scientists who studied the effect of climate change on life expectancy using cross-national data from 191 countries covering the period 1940–2020 and concluded that if the annual average temperature rises by 1°C, then it decreases by 0 ,44 years (PLOS CIMATE 2024 “Advancing action on the UN Sustainable Development Goals“).
Experts point out that climate change is expected to disproportionately reduce the life expectancy of women compared to that of men. “Global life expectancy increased significantly between 1960 and 2020 from 55 to 72 years. At the same time, the global average life expectancy for men increased significantly from 48 to 70 years and the global average life expectancy for women increased significantly from 52 to 74 years,” the scientists report and explain that this is due to access to abundant and more nutritious food, clean water, better hygiene and advanced medical care along with innovations in antibiotics and vaccines.
As for women, the study reports that an increase in per capita income has had a positive effect on life expectancy at birth for girls. However, the rise in temperature has a statistically significant negative effect on their life expectancy. In more detail it is predicted that if the annual average temperature increases by 1°C, life expectancy at birth for girls will decrease by -0.91 years or by about 10 months, all other factors remaining the same.
At the same time, if the annual climate change index increases by 10 points, life expectancy at birth for boys will decrease by 0.40 years or 5 months. In contrast, life expectancy at birth for girls will decrease by 0.60 years or 7 months. In conclusion, the researchers point out that the relationship between the climate change index and life expectancy highlights the urgent need to address the environmental crisis, calling on countries to take immediate action to limit global warming and protect the health of the population.
Body and high temperatures
So why is excessive heat so dangerous to the human body? According to the World Health Organization (WHO) (“Heat and health“) prolonged periods of high day and night temperature conditions cause heat stress in the human body, increasing the risk of illness and death from exposure to heat as it puts a strain on many vital organs: extreme heat impairs heart function, blurs memory, causes rapid dehydration and if conditions are severe, eventually leads to death due to the stress on the body as it tries to maintain its temperature. Thus, extreme temperatures often aggravate patients with chronic diseases such as cardiovascular, mental, respiratory diseases, and cause acute kidney injury.
The result of overheating is also the intense rains that are accompanied by conditions that facilitate the transmission of infectious diseases. These are transmitted through water, air and food and is a process involving three active agents, namely pathogen, host and a vulnerable transmission environment. Earlier research (PubMed Central, 2019) highlighted the increasing role of warm and unstable climate change in accelerating the global emergence, outbreak and redistribution of infectious diseases transmitted by insects such as dengue fever, cholera, malaria.
So a plan of action is more necessary than ever as the planet seems to be reaching its limits. However, until a substantial solution is found, experts recommend taking self-protection measures such as avoiding sun exposure during difficult hours or taking cool showers to lower body temperature.
