Reading Scott and Scurvy, a fascinating post on Idle Words about the scurvy which plagued Robert Scott's 1911 expedition to the South Pole:
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?
It's a fascinating story of how medical practice which lacks knowledge of underlying causes can become distorted over time. It's also kind of heartbreaking to read about the polar missions failing again and again all because they're working from the wrong model of scurvy as a disease.