Civil War (1861-65). In the early 1900s it was thought to be an infectious disease, but studies conducted by public health physician Joseph Goldberger at the Milledgeville State Hospital (later Central State Hospital) in Georgia showed that it was related to diet. Death statistics indicate that pellagra may have been one of the most severe nutritional deficiency diseases ever recorded in the United States. Symptoms include dermatitis, diarrhea, inflammation of the mucous membranes, and even dementia. Pellagra can flare in strong sunlight. Left untreated, the condition results in death.
The incidence of pellagra increased greatly in the early twentieth century, during the Progressive Era. In 1909 more than 1,000 estimated cases were reported from thirteen states. By 1911 pellagra was reported in all but nine states, and the number of cases increased ninefold. From 1906 to 1940 approximately 3 million cases and 100,000 deaths were attributed to this disease. It was most prevalent in the southern states, where income level was low and most of the available land was used for such cash crops as cotton and tobacco rather than food crops. By 1920 pellagra had became a serious illness in Georgia, where 432 deaths were attributed to the disease. During 1928-29, at its peak incidence, pellagra was the eighth or ninth leading cause of death besides accidents in the South.
Economic recovery and the enrichment of flour with niacin improved diet and health in areas where pellagra had been common. This made possible the elimination of pellagra by the end of the 1940s.