Nicholas Christakis

Nicholas A. Christakis (US: /ˌnɪkələs krɪˌstɑːkɪs/ NIK-ə-liss kriss-TAK-iss) (born May 7, 1962) is an American sociologist and physician known for his research on social networks and on the social, economic, biological, and evolutionary determinants of human welfare (including the behavior, health, and capabilities of individuals and groups). He is the Sterling Professor of Social and Natural Science at Yale University, where he directs the Human Nature Lab. He is also the co-director of the Yale Institute for Network Science.

Christakis was elected a Fellow of the National Academy of Sciences in 2024. He was elected a Fellow of the National Academy of Medicine in 2006; of the American Association for the Advancement of Science in 2010; and of the American Academy of Arts and Sciences in 2017. In 2021, he received an honorary degree in economics from the University of Athens, Greece. He was awarded the Barry Prize for Distinguished Intellectual Achievement by the American Academy of Sciences and Letters in 2024.

In 2009, Christakis was named to the Time 100, Time magazine's list of the 100 most influential people in the world. In 2009 and again in 2010, he was named by Foreign Policy magazine to its list of top global thinkers.

Christakis' parents are Greek. They had three biological children and then adopted two others, an African-American girl and a Taiwanese boy. His father was a nuclear physicist turned business consultant and his mother a physical chemist turned psychologist.

Christakis was born in New Haven, Connecticut in 1962 when both his parents were Yale University graduate students. His family returned to Greece when he was three, and Greek became his first language. He returned to the United States with his family at age six and grew up in Washington, D.C. He graduated from St. Albans School.

Christakis obtained a B.S. in biology from Yale University in 1984, where he won the Russell Henry Chittenden Prize. He received an M.D. from Harvard Medical School and an M.P.H. from the Harvard School of Public Health in 1989, winning the Bowdoin Prize.

In 1991, Christakis completed a residency in Internal Medicine at the University of Pennsylvania Health System. He was certified by the American Board of Internal Medicine in 1993. He obtained a Ph.D. in sociology from the University of Pennsylvania in 1995. While at the University of Pennsylvania as a Robert Wood Johnson Clinical Scholar, he studied with Renee C. Fox, a distinguished American medical sociologist; other members of his dissertation committee were methodologist Paul Allison and physician Sankey Williams. His dissertation was published as Death Foretold, his first book.

In 1995, Christakis started as an assistant professor with joint appointments in the Departments of Sociology and of Medicine at the University of Chicago. In 2001, he was awarded tenure in both Sociology and Medicine. He left the University of Chicago to take up a position at Harvard in 2001. Until July 2013, he was a professor of sociology in the Department of Sociology in the Harvard Faculty of Arts and Sciences; a professor of medical sociology in the Department of Health Care Policy and a professor of medicine in the Department of Medicine at Harvard Medical School; and an attending physician at the Harvard-affiliated Mount Auburn Hospital.