This very topical information for the summer season is reported by The Guardian.
It is known that the smell of sweat is not emitted directly from the human body. The organic substances thiols, which have a characteristic sulfurous odor, are a by-product that forms when microbes absorb other compounds present on the skin.
Researchers at the University of York, who published their paper in Scientific Reports, traced the source of the unwashed armpit odor to a specific enzyme in a specific microbe living in the armpits.
As it turned out, most microbes living on the skin are not involved in the production of thiols. One species, Staphylococcus hominis, is to blame: by ingesting an odorless compound called Cys-Gly-3M3SH, which is secreted by apocrine glands in the armpit, it produces fetid fumes.
As the study's authors popularly explain, “bacteria take a molecule, eat some, and spit out the rest, and this is one of the key molecules that we recognize as body odor. Our noses are extremely good at capturing thiols even at extremely low thresholds. They have a very characteristic smell of cheese or onions that cannot be confused with anything. They are incredibly caustic".
Why do our bodies smell sweat? This is not yet clear. Humans probably inherited the stench-producing microbes from their primate ancestors. And since the apocrine glands begin to secrete caustic compounds during puberty, it can be assumed that this is due to the process of procreation.
“All we can say is that the process is not new,” the scientists say. - The smell of the body has definitely accompanied humanity in the process of evolution and, it is possible, played an important role in this. Before we started using deodorants and antiperspirants, and this happened only 50-100 years ago, everyone smelled". The study by British scientists was carried out with the participation of the cosmetics company Unilever.
This means that in the future, we may be able to have deodorants that target the sweat-producing microbes, leaving the rest of the underarm microbial community alone.