At least, according to Markus Appel, an associate professor at the Johannes Keppler University of Linz, Austria. He conducted an experiment where the subjects read a really dumb story about a really stupid fellow and then gave them a general knowledge test. It looked like those who read the tale of the idiot did worse at the general knowledge test than those who didn't. It was not known whether the test subjects were daft to begin with.
If that is so, will reading urban fantasy make me into a supernatural monster?
Anyway, who cares what is the capital of Libya?