
“Be careful about reading health books. You may die of a misprint.”
Attributed to Markus Herz by Ernst von Feuchtersleben, Zur Diätetik der Seele (1841), p. 95 http://books.google.com/books?id=FLc6AAAAcAAJ&pg=PA95&dq=%22Lieber+Freund+Sie+werden+noch+einmal+an+einem+Druckfehler+sterben%22. First attributed to Twain in 1980s, as in The 637 best things anybody ever said, (1982), Robert Byrne, Atheneum. See talk page for more info.
Misattributed
Variant: Be careful about reading health books. You may die of a misprint.