I found this story on @HistoryWeird's blog here. The original source was Dr F. Waetzold's “Le piano et névroses” in Journal d'Hygiene, January 5th 1899.
"In 1899 German physician Dr F. Waetzold published a short essay claiming that playing the piano was contributing to an increase in mental disorders among teenage girls and young women. According to Waetzold his research had uncovered some alarming links between piano-playing and neurotic disorders.
"One condition prominent among young pianists was chlorosis or ‘green sickness’, an anaemic fatigue thought by many Victorian physicians to be a product of unfulfilled sexual excitement. Girls who studied the piano before the age of 12, wrote Waetzold, were six times more likely to contract chlorosis or neuroses than those who did not. His solution was simple:
"'It is necessary to abandon the deadly habit of compelling young girls to hammer on the keyboard before they are 15 or 16… Even at this age the exercise should be permitted only to those who are really talented and possessed of a robust temperament.'
"Choosing another instrument was not necessarily an option, according to Waetzold, because 'studying the violin appears to produce even more disastrous results'. It seems that Dr Waetzold was not a music fan – or perhaps he lived within earshot of some decidedly untalented young musicians."
Clearly he's seen the movie Stoker. Y'all know which scene I'm talking about.