Scurvy: medical break-throughs that are later forgotten
This kind of thing really scares me:
They had a theory of the disease that made sense, fit the evidence, but was utterly wrong.
I am interested in cases where technology goes backwards and important scientific break throughs are forgotten, so this story about scurvy got my attention:
Now, I had been taught in school that scurvy had been conquered in 1747, when the Scottish physician James Lind proved in one of the first controlled medical experiments that citrus fruits were an effective cure for the disease. From that point on, we were told, the Royal Navy had required a daily dose of lime juice to be mixed in with sailors’ grog, and scurvy ceased to be a problem on long ocean voyages.
But here was a Royal Navy surgeon in 1911 apparently ignorant of what caused the disease, or how to cure it. Somehow a highly-trained group of scientists at the start of the 20th century knew less about scurvy than the average sea captain in Napoleonic times. Scott left a base abundantly stocked with fresh meat, fruits, apples, and lime juice, and headed out on the ice for five months with no protection against scurvy, all the while confident he was not at risk. What happened? …
This pattern of fresh meat preventing scurvy would be a consistent one in Arctic exploration. It defied the common understanding of scurvy as a deficiency in vegetable matter. Somehow men could live for years on a meat-only diet and remain healthy, provided that the meat was fresh.
This is a good example of how the very ubiquity of vitamin C made it hard to identify. Though scurvy was always associated with a lack of greens, fresh meat contains adequate amounts of vitamin C, with particularly high concentrations in the organ meats that explorers considered a delicacy. Eat a bear liver every few weeks and scurvy will be the least of your problems.
But unless you already understand and believe in the vitamin model of nutrition, the notion of a trace substance that exists both in fresh limes and bear kidneys, but is absent from a cask of lime juice because you happened to prepare it in a copper vessel, begins to sound pretty contrived.
Doctors of the era looked at this puzzling evidence and wondered. Other diseases had recently been shown to have their source in bacterial infection. The bacterial model was new, and had already had spectacular success in identifying and treating diseases like typhus, tuberculosis, and cholera. What if the cause of scruvy had also been misunderstood? What if instead of a deficiency disease, scurvy was actually a kind of chronic food poisoning from bacterial contamination of meat? Thus was born the ptomaine theory of scurvy, and Koettlitz became its enthusiastic backer