Vitamin C megadosage with and published two articles discussing the possible relationship between lipoprotein and vitamin C with Pauling. He is an active proponent and publicist for high-dose vitamin C. Pauling's and Rath's extended theory states that deaths from scurvy in humans during the ice age, when vitamin C was scarce, selected for individuals who could repair arteries with a layer of cholesterol provided by lipoprotein(a), a lipoprotein found in vitamin C-deficient species. Stone and Pauling believed that the optimum daily requirement of vitamin C is around 2,300 milligrams for a human requiring 2,500 kcal a day. For comparison, the FDA's recommended daily
Scurvy caused by ptomaine, a waste product of bacteria, particularly in tainted tinned meat. Infantile scurvy emerged in the late 19th century because children were being fed pasteurized cow's milk, particularly in the urban upper class. While pasteurization killed bacteria, it also destroyed vitamin C. This was eventually resolved by supplementing with onion juice or cooked potatoes. By the early 20th century, when Robert Falcon Scott made his first expedition to the Antarctic (1901–1904), the prevailing theory was that scurvy was caused by "ptomaine poisoning", particularly in tinned meat. However, Scott discovered that a diet of fresh meat from Antarctic seals