You probably won’t recognize it, but we know you all have done it, especially when you were younger. It is more than common to see a child, staring into space, conscientiously exploring his nose, then eating what he finds there. If this spectacle disgusts you as an adult, it is nevertheless common to little ones, enough for science to question this shared trait. For some researchers, we must look to our primate cousins, chimpanzees in the lead, who are also adept at this gathering.
However, behind this socially constructed disgust, science struggles to provide precise figures. The practice, although suspected of being universal, remains one of the last virgin territories in behavioral research. A 2001 study, carried out in India among 200 adolescents, nevertheless broke the silence: while almost all of the respondents admitted to picking their noses, around nine of them confessed to regularly eating the fruit of their peach.
The last vestige of our wild state?
If the act of picking one’s nose responds to a natural need to clear one’s airways, the consumption stage remains more mysterious. Some researchers, like biochemist Scott Napper, put forward the following hypothesis: this “mucophagy” could be an archaic lever of our immune system.
By ingesting weakened infectious agents filtered through his nose, the child would train his natural defenses, a sort of natural and daily vaccine. “From an evolutionary point of view, we evolved in very unhygienic conditions”recalls the researcher, whose theory remains to be proven.
Beyond biology, there is an almost intimate dimension to this childish perseverance. It is the conquest of a personal territory, an extraction of oneself which defies the conventions of modern politeness. Children, still impervious to the dictates of decorum, act out of pure sensory pragmatism. The salty taste, the unique texture, everything combines to transform organic waste into a snack. So, is this just pure gluttony?
Currently, no major investigation has been launched to quantify this behavior in adults, although experts agree that the transition to maturity simply shifts the practice to the private sphere. What is perceived as a dirty habit could well be the vestige of a time when man, faced with a hostile environment, tried to put all the chances of survival on his side.
