(1912–2000), German-American biochemist and Nobel laureate, born in Neisse, Germany (now Nysa, Poland), and educated at the Technical University of Munich and Columbia University, where he received his Ph.D. in 1938. After teaching biochemistry at the University of Chicago from 1946 to 1954, Bloch became a professor of biochemistry at Harvard University, a position he held until his retirement in 1982. He was also a professor (1979–84) at Harvard’s School of Public Health.

Prior to his move to the U.S. in 1936, Bloch had studied the biochemistry of tubercle bacilli in Switzerland; in 1938 he began research at the College of Physicians and Surgeons at Columbia in the isotopic analysis of cell metabolism. At the University of Chicago, Bloch demonstrated that all carbon atoms of cholesterol originate in the carbon molecules of acetate. With others, he determined that a chemically active form of acetate, acetyl coenzyme A, is converted through a series of chemical changes into cholesterol. This research and the independent research of the German biochemist Feodor Lynen clarified the role of acetic acid as a building block for cholesterol and fatty acids.

Bloch and Lynen shared the 1964 Nobel Prize in medicine or physiology for “their discoveries concerning the mechanisms and regulation of cholesterol and fatty-acid metabolism.”