Hunter Dukes in The Public Domain Review:
It was dangerous to be a man of letters in the eighteenth century. All that rumination; such single-minded concentration; countless hours hunched over the escritoire. “Some men are by nature insatiable in drinking wine, others are born cormorants of books”, wrote the Swiss physician Samuel-Auguste Tissot in An Essay on Diseases Incidental to Literary and Sedentary Persons (1768). As with the reckless consumer of claret, an overindulgence in books could have devastating consequences for the mind and body.
Across his essay, Tissot offers hundreds of examples of men who read too much, studied too hard, and consumed knowledge to the point of madness. There is the young man who developed an allergy to reading: “if he read even a few pages, he was torn with convulsions of the muscles of the head and face, which assumed the appearance of ropes stretched very tight.” And the man whose laser focus effected hair removal: “his beard fell first, then his eye-lashes, then his eye-brows, then the hair on his head, and finally all the hairs of his body”. There is Nicolas Malebranche, who was gripped with “dreadful palpitations” upon looking into Descartes’ Treatise on Man, and an unnamed Parisian rhetorician, who “fainted away whilst he was perusing some of the sublime passages of Homer.”
More here.