It wasn't a perfect study; only about a quarter of those surveyed responded, and those who already had a personal interest in nose picking may have been more likely to complete and return the survey. Still, it underscored the likelihood that nose picking, despite its cultural taboos, is pretty widespread.

Young habit

Five years later, doctors Chittaranjan Andrade and BS Srihari of the National Institute of Mental Health and Neurosciences in Bangalore, India, decided to look a little deeper into nose-picking. They reasoned that most habitual behaviours are more common among kids and teenagers than among adults, so it made sense to survey younger populations rather than older populations, to get a sense for how prevalent nose picking might be. In addition, knowing that the Wisconsin study suffered from a possible response bias, they distributed their surveys in school classrooms, where they would have a much higher likelihood of getting a representative sample. They focused on four schools within Bangalore, one catering to children from families of lower socioeconomic status (SES), two whose students tended to come from middle-class families, and a fourth school where students came from higher-earning households.

In all, Andrade and Srihari compiled data from 200 teenagers. Nearly all of them admitted to picking their noses, on average four times per day. That's not all that enlightening; we knew this. But what are interesting are the patterns. Only 7.6% of students reported sticking their fingers into their noses more than 20 times each day, but nearly 20% thought they had a “serious nose-picking problem”. Most of them said they did it to relieve an itch or to clear out nasal debris, but 24 of them, i.e. 12%, admitted that they picked their nose because it felt good.