When the thermometer soars, many dream of staying dry. However, sweating is far from being a simple summer inconvenience. This natural mechanism allows the body to maintain a stable temperature despite extreme heat and limits the risks associated with overheating.
Questioned on Matinale TF1, dermatologist Dr. Marie Jourdan recalls that perspiration is above all “our internal air conditioning“Without it, the body would have much more difficulty dissipating the heat accumulated during a heatwave.
Why does the body start to sweat when it is very hot?
As soon as the blood temperature rises, the brain triggers an immediate reaction. It sends signals to millions of sweat glands across the skin to produce sweat.
As Dr. Marie Jourdan explains, “when the brain senses that the blood is a little too hot, it sends little messages all over the skin so that it sweats, to lower the temperature of the human body“.
This sweat is composed mainly of water and salt. By evaporating on the surface of the skin, it absorbs part of the body’s heat, which gradually reduces body temperature.
What is sweat made of?
Contrary to popular belief, sweat does not only contain water. It also contains plasma as well as various minerals eliminated by the body.
Once on the surface of the skin, it naturally mixes with sebum, bacteria present on the epidermis and dead cells. This combination can sometimes cause irritation or clog certain pores, especially when sweating is profuse for several days.
Why it is essential to stay well hydrated
Although sweating is essential to combat the heat, it also causes a significant loss of fluid. During a heatwave, it is therefore essential to drink regularly in order to compensate for this loss of water and allow the body to continue to regulate its temperature effectively.
Good skin hygiene is also recommended when episodes of high heat are prolonged, in order to limit irritation linked to the accumulation of sweat, sebum and impurities.