Josef, Baron von Mering (28 February 1849, in Cologne – 5 January 1908, at Halle an der Saale, Germany) was a German physician.
Working at the University of Strasbourg, Mering was the first person to discover (in conjunction with Oskar Minkowski) that one of the pancreatic functions is the production of insulin, a hormone which controls blood sugar levels.
Mering was curious about the pancreas, a comma shaped organ, situated between the stomach and the small intestine.
Mering realised that this was a symptom of diabetes and tested the urine, which was found to be high in sugar, confirming his suspicion.
Josef von Mering helped to discover barbiturates, a class of sedative drugs used for insomnia, epilepsy, anxiety, and anesthesia.