From the moment Marie Curie announced the existence of radium, the strange new element captured the imagination of the American public. Radium, it seemed, could do anything. It gave off its own light and heat and appeared to realize the ancient alchemical dream of transmutation. It also showed promise as a medicine. The press ran with the idea that radium was a panacea that would cure everything from cancer to wife-beating. Soon it became impossible for the public to know what to believe when it came to radium and its effects on the body. Patent medicine companies exploited the murkiness surrounding ideas about radium, marketing a slew of products that claimed to harness the element’s healing and energizing powers. Meanwhile, physicians made slow, careful progress in defining the parameters of radium therapy, narrowing their focus to cancer. The popularity of radium patent medicines peaked in the 1920’s when hundreds of thousands of Americans purchased one or more of the dozens of radium products that proliferated at the time. Government regulators and members of the medical establishment sought to push these products from the market, but loopholes in the regulatory apparatus created under the Pure Food and Drug Act of 1906 allowed many of these companies to operate freely. Two scandals—the saga of the “Radium Girls” and the death of Eben Byers, a well-known industrialist who died after drinking over 1000 bottles of a radioactive tonic called Radithor—damaged radium’s image in the 1920’s and 1930’s. By the late 1930’s, strengthened regulatory laws helped push radioactive products from the marketplace. During World War II, scientists discovered artificial isotopes that proved more effective and less expensive than radium in the treatment of disease. For decades Americans had struggled to make sense of a scientific discovery that seemed to challenge fundamental ideas about the nature of the body and its relationship to the physical world. The ambiguities surrounding the element posed a unique challenge to progressive ideals of expertise and professionalization while providing a malleable image of energy and health that a variety of commercial interests could deploy. / text