Overuse is not a recent phenomenon. The past is full of examples of overuse that we have labeled bad science, ignoring the potential lessons for modern medicine. In the middle ages, physicians bled patients with leeches and dosed them with mercury. Although we scoff now, these were accepted practices. Oliver Wendell Holmes bucked convention in 1860 at the Massachusetts Medical Society when he stated "if the whole material medica, as now used, could be sunk to the bottom of the sea, it would be better for mankind — and all the worse for the fishes." More recently discarded practices include thalidomide for nausea in pregnancy after it led to thousands of babies with massively deformed arms or legs in the 1950s. Likewise, the female hormone estrogen was widely used by older women in the 1990s until a randomized-controlled trial showed it increased cancer and heart disease (akin to current use of the male hormone testosterone, which has similar possible harms). These examples are obvious in retrospect, but the true benefit and harms of treatment are often not clear in the present.