What happens to the body in a house without heat?
In Italy, it was decided by law that the maximum (average) temperature that had to be maintained in the houses during the winter should be 20 degrees, with a maximum allowed fluctuation of two degrees.
With the energy crisis caused by the Russian occupation of Ukraine, the Draghi government lowered it to 19 degrees, which is the temperature usually recommended to combine physical well-being and respect for the environment.
Without warming, temperatures would drop much further, to the point where they would become harmful to humans and justify the rise in mortality calculated by the Economist.
BBC science journalist James Gallagher, who took part in an experiment at the University of South Wales to study the effects of cold on the body, shows what happens to the body when it gets too cold.
The researchers placed him in a microchamber and lowered the temperature to ten degrees, monitoring his vital parameters.
"Ten degrees is the average temperature that people who can't afford to heat their homes live in winter," says Professor Damian Bailey.
"It looks mild, but it's a real physiological challenge," he adds. The temperature at which the human body works is actually much higher, it is 37 degrees, and maintaining it when there is a similar thermal change is difficult for the organism.
Gallagher started the experiment at a temperature of 21 degrees. When the environment cooled to 18 degrees, the hairs on his body literally stood up.
"Science tells us that 18 degrees is the tipping point where the body starts working to protect its internal temperature," explains Professor Bailey.
One of the first tricks the body has is vasoconstriction: blood vessels close to keep blood warm to organs essential for survival. It is the reason why the ends of the limbs become white and cold. The temperature of Gallagher's hands and feet dropped an average of two degrees.
At the same time, blood pressure rises and the blood becomes thicker, increasing the risk of stroke and heart attack, which are actually more common in winter. Your breathing rate and heart rate also increase as your body burns more calories. It is the extra work the body has to do to maintain its basal temperature. And he pays the consequences.
During the experiment, Gallagher underwent a cognitive test and had more difficulty solving the exercises than a similar test performed at 21 degrees of ambient temperature.
"Less blood gets to the brain, so there's less oxygen and less glucose, and that has a negative impact," says Bailey.
"The tests clearly suggest that cold is more deadly than heat, there are more deaths caused by cold waves than those caused by heat waves," he adds. Although the tendency of the media is to warn of the dangers of the heat.
These are not the only risk factors: the cold makes it easier for viruses to survive and spread and weakens our immune response (and the reason why we get sick more in winter). The BBC journalist stayed in ten degrees for only half an hour, but he had no warm clothes to cover himself.
It is clear that by dressing up or staying under the covers you can partially protect yourself from the cold. But a temperature lower than 18 degrees is still difficult for the body. And this explains the relative increase in mortality.