Small smells can communicate valuable information. In many animals, volatile molecules called pheromones are used to send signs to other individuals of the same species, to influence their behavior, or to report the presence of dangers or the availability for mating. There is a lot of discussion whether this happens, or not, also in Homo Sapiens. And today a study by the University of Tokyo brings new tests in favor: the research, published in the magazine Science, seems to demonstrate that the smell emitted by the female body during the ovulation period influences male perception, making it more likely that they find the appearance and perfume of the woman in question attractive.
The debate on human pheromones
The possibility that pheromones are also used by our species as a form of chemical communication, we said, is very debated. Several research in the past have achieved results that seem to demonstrate the possibility that the smell, male and female, manages to influence the predispositions of the other sex. However, not all researchers are willing to accept this explanation, also because the effects – if present – are certainly less strong than those that are seen in other animal species, in which culture and social norms play a less prominent role on behaviors. And above all, because of no specific substance emitted by the human body, the ability to work as a pheromone has ever been demonstrated in an incontrovertible way.
In their study, Japanese researchers attempted to do this: identify specific substances present in female sweat that can exert some effect on male behavior. To do this, they used a defined technique chascromatography-impractor of mass, one of the most advanced chemical analysis technologies, which allows to separate and identify all the compounds contained in a gas.
The 21 women of the experiment
21 women of fertile participated in the experiment. The researchers collected sweat samples during each of the phases of the menstrual cycle. And using their analysis techniques, they identified the substances present, and in particular those whose levels tended to increase in the period of ovulation.
“We have identified three components of the body smell that increase during the period of ovulation”, explains Kazushige Touhara, professor of applied chemical biology of the University of Tokyo. “When men sniffed a mixture of these compounds with a standard armpit smell they evaluated him less unpleasant, and placed in front of female images they found them more attractive”.
What the research has shown
The three compounds have also shown that they have a relaxing power towards male subjects, and the ability to suppress the increase in amylase in their saliva, a biomarker used to evaluate the presence of stress. According to the authors, the results are proof that body smell can somehow contribute to communication between men and women.
So are they human pheromons? On these, Japanese scientists are more cautious, also to avoid being dragged into the controversies that have always accompanied similar statements in the past. “The pheromone is classically defined as a species-specific chemical substances that induces certain behavioral or physiological responses-concludes Touhara-. And with this study we cannot establish whether the axillary smells that we have discovered are species-specific species. We focused mainly on their behavioral and physiological impact, in this case, the reduction of stress and the change in the male evaluation of a face. We can say that they could be composed with effects similar to those of pheromones “.
Read the Sciences section of Toray.it