 After learning preceptorship in gastroenterology from this man, the next three years became very fruitful for Janowitz, who during those years served as gastroenterologist in France and Germany, and was eventually sent home with a rank of a major.Following the war, he resumed his studying, earning a Master's degree in physiology from Columbia University College of Physicians and Surgeons.In 1947, at the age of 32, Janowitz became a CUCPS resident.