Insulin (1921)

Insulin's 1921 isolation by Frederick Banting and Charles Best at the University of Toronto immediately outperforms the discovery of penicillin in life-saving impact: it cut diabetes mortality rates by more than 50% within a year. Before insulin, Type 1 diabetes was a death sentence, with patients often dying within two years; the only treatment, a near-starvation diet, could barely extend life by a year. This breakthrough transformed a fatal condition into a manageable chronic one. The first human recipient, a 14-year-old boy in a diabetic coma, made a full recovery in January 1922. Insulin remains the cornerstone of diabetes therapy, saving millions of lives annually.