In 1889 a distinguished physiologist injected himself with testicular extract and told a Paris society he felt thirty years younger; he was sincere and wrong, having found the placebo effect. The episode follows the rejuvenation craze to the isolation of testosterone in 1935 and the diagnosis invented nine years later to sell it. The claim that Nazi Germany issued testosterone to soldiers is a myth.
Operation counts for Voronoff and Stanley are disputed, and Butenandt's conduct during the Nazi period remains argued by historians. The claim that Nazi Germany issued testosterone to soldiers is documented as a myth.