Hopkins, Frederick Gowland
Frederick Gowland Hopkins (1861-1947) is credited with the discovery of vitamins and their function in the diet. Thanks to his research, we now understand the importance of these substances in promoting health and preventing disease.
Born in Sussex, England, Hopkins had a lonely and unhappy childhood. He was brought up by his widowed mother and an unmarried uncle who tended to ignore him. When Hopkins was 17, his uncle chose a career in insurance for him and for several years he dutifully gave in to his uncle's wishes. At the same time, however, he also took part-time courses in chemistry at the University of London, eventually getting his degree.
In 1888, already 27 years old, Hopkins received the small inheritance that finally enabled him to enter medical school at Guy's Hospital in London. After getting his doctoral degree in 1894, Hopkins joined the staff of Guy's Hospital and taught for several years. In 1898 he was invited to teach physiology and anatomy at Cambridge University and it was at Cambridge that his long, distinguished career really began.
In 1901, while working with S.W. Cole, a student at Cambridge, Hopkins discovered tryptophan, an important amino acid, and was able to isolate it from protein. A few years later Hopkins demonstrated that tryptophan and certain other amino acids could not be manufactured in the body from other nutrients but had to be supplied the diet. By so doing, he laid the foundation for the concept of the essential amino acids necessary for proper body functioning.
After his work with tryptophan, Hopkins's primary interest became the study of diet and its effect on metabolism (the physical and chemical processes necessary for maintaining the body). At the time, nutritional science was in a fairly primitive state. Most researchers confidently believed that a well-rounded diet consisted of the proper mixture of fats, proteins, carbohydrates, mineral salts, and water, and that the so-called diet-linked illnesses—such as beriberi or scurvy—were caused by some toxic substance in certain foods.
Studying the literature—including reports by Christiaan Eijkman (1858-1930) that polished rice seemed to cause beriberi (a nerve disease), while unpolished rice effected a cure—Hopkins began to have serious doubts about this nutritional theory.
Hopkins had already noticed that his laboratory rats failed to grow on a diet of artificial nutrients, but grew rapidly when he added tiny amounts of cow's milk to their daily rations. He suspected that normal food must contain substances missing from the pure fats, proteins and carbohydrates routinely used in nutritional studies. Hopkins called these substances "accessory food factors" and decided that they were necessary for growth. His two papers on the subject, in 1906 and 1912, are considered the first explanations of the concept of vitamins.
For their pioneering work in vitamin research, Hopkins and Eijkman received the 1929 Nobel Prize in medicine. Hopkins was knighted in 1925 and received numerous other awards in the 1920s and 1930s. He was a great inspiration to all of his students, many of whom became professors. Hopkins died in Cambridge in 1947.