Despite his interest in health, Cummings was also a methamphetamine addict from the mid-1950s until the end of his life. In 1954, while in New York to star in the "Westinghouse Studio One" production of "Twelve Angry Men", Cummings began receiving injections from Max Jacobson, the notorious "Dr. Feelgood". His friends Rosemary Clooney and José Ferrer recommended the doctor to Cummings, who was complaining of a lack of energy. While Jacobson insisted that his injections contained only "vitamins, sheep sperm, and monkey gonads", they actually contained a substantial dose of methamphetamine.