Radio waves are attenuated by human tissue depending on their frequency but I would be surprised if one person's body produced a total cut off. I have noticed one door in our house that seems to weaken the signal if closed and of course WiFi doesn't necessarily penetrate equally well to all corners of a house because of attenuation by walls, especially solid ones.
4 Years On…..Health-wise, Has Anything Changed?
Gary Glitter programme Tuesday
To think that London, or anywhere else for that matter, does not belong to any one demographic