Lester Breslow (March 17, 1915 in Bismarck, North Dakota, USA – April 9, 2012 in Los Angeles, California, USA) was an American physician who promoted public health. Breslow's career had a significant impact. He is credited with pioneering chronic disease prevention and health behavior intervention. His work with the Human Population Laboratory in the Alameda County Study established the connection between mortality and lifestyle issues like exercise, diet, sleep, smoking, and alcohol. He has been called "Mr. Public Health".