Pellagra, a disease prevalent in the American South post-Civil War, was identified as non-contagious and related to diet deficiencies in milk, meat, or eggs by Joseph Goldberger through experiments on prisoners. While contagious transmission was ruled out, the specific dietary deficiency was still undetermined but termed the pellagra-preventive factor.
A visual chronology of Asimov's ~1500 scientific inventions and discoveries.
