Yes, that is true. Half of the Smiths family changed their names to Jones when their cousin, W.H., opened his first newsagent. The reason for this defection? They were alergic to newspapers. They developed a black rash on their fingers whenever they came into contact with one.
Definitely, I tried it myself. Not sure about the TEETH (teath?!) thing though as all mine fell out when I was 11 as a result of an accident with a bag of sherbet lemons.