- President's Medal for Excellence (1990)
- Naming of Day Lecture Hall
- Bloomington, Indiana
- Presenter: Thomas Ehrlich
- National Academies (1951)
- American Association for the Advancement of Science
Born to John Freeman Day and Minta E. Spencer in Monroe County, Iowa, on October 8, 1906, Harry attended Cornell College in Mount Vernon, Iowa, where he graduated with an AB in chemistry. He received a doctorate of science in biochemistry from Johns Hopkins University, Baltimore, in 1933. Following a year as a National Research Council Fellow, he went to Yale as a General Education Board Fellow and then returned as an associate in the Department of Biochemistry at Johns Hopkins (1936–40). There he established a career in nutrition, working with Elmer V. McCollum and C. Orient-Kieles on THE NEWER KNOWLEDGE OF NUTRITION (5th ed, 1939).
Day joined the chemistry faculty of Indiana University in 1940 as an assistant professor, and in 1950 he became a full professor. He was chairman between 1952 and 1962. Day also devoted considerable time and energy in writing DEVELOPMENT OF CHEMISTRY AT INDIANA UNIVERSITY IN BLOOMINGTON, a book in which he describes the department’s history up to 1991. In addition to many committee assignments, he was associate dean for research and advanced studies from 1967 to 1972 and special assistant in the office of research and development from 1973 to his retirement in 1976.
He received the IU President’s Medal for Excellence in 1990 and the university’s Distinguished Service Award in 1993. Throughout his academic career, he was a pioneer in zinc research and authored more than 200 scientific publications. Perhaps the accomplishment for which he is best remembered is his contribution to the development of Crest toothpaste. In the 1950s while at IU, Day, J.C. Muhler, and W.H. Nebergall conducted research on the effects of fluorides in the reduction of dental caries. The result of this research was the first dentifrice containing stannous fluoride, namely Crest toothpaste. Day’s interest in nutrition expanded to include significant contributions to the American Institute of Nutrition; American Institute of Biological Chemists, where he served as president; and the Indiana Academy of Science. He was named a Sagamore of the Wabash in 2004.
Throughout his career, Day mentored hundreds of students and often provided financial support to enable them to continue their education. Day was interested in wherever he thought he could be of service not only professionally, but locally through civic organizations such as Kiwanis and Bloomington Hospital, where he was the first male to serve on the Women’s Board. An active Republican, he served on the Bloomington City Council in the 1960s. Day has also been a moving force within the First United Methodist Church, serving as a trustee for a number of years. He was elected to the city council and served in that body for eight years until 1971. For his contributions to the chemistry department, the university, and the city, Day was elected to the Monroe County Hall of Fame. Moreover, the main lecture hall in the Chemistry Building as well as a lectureship bears his name.
He died in 2007.