How the cure for scurvy was found and lost again

HostMost of us think of medical history as a straight line moving forward, but sometimes we find an answer and then just let it slip through our fingers. Back in the days of wooden sailing ships, scurvy was a bigger threat to sailors than any storm or sea battle. It was a terrifying way to die because your body basically started to come apart at the seams. It could even melt down old scar tissue and make wounds you had years ago suddenly pop back open.

HostWe know now it was just a lack of fruit, but why did it take hundreds of years for that simple fix to actually stick?

GuestIt's one of the strangest gaps in history because the first real test to find a cure happened way back in seventeen forty-seven. A doctor named James Lind took twelve sick sailors and divided them into groups to see what would help. He gave some of them vinegar, some got sea water, and one lucky pair got oranges and lemons. The guys eating the fruit got better almost instantly. It was a clear win, but the problem was that Lind didn't really understand why it worked.

GuestAt that time, doctors thought scurvy was caused by things like damp air or bad digestion that made the body start to rot from the inside. Lind believed the fruit only worked because it was very acidic. To make the cure easier to carry on long trips, he decided to boil the juice down into a thick, heavy syrup. But we know now that high heat destroys Vitamin C. He was basically cooking the life right out of his own cure. When other doctors tried his boiled syrup and it failed, they just assumed Lind was wrong about the fruit.

HostBut surely someone noticed that fresh fruit worked even if the cooked syrup did not. It seems hard to ignore people getting better right in front of you.

GuestYou would think so, but the medical world back then was very set in its ways. For forty years after that first test, the leaders of the Navy were flooded with all kinds of other cures that sounded more scientific to them. High-ranking doctors pushed for things like malt, vinegar, or even watered-down sulfuric acid. They thought these things would balance out the internal chemistry of the body.

GuestSee, they didn't have a concept for what we call a nutritional deficiency. They didn't think a disease could be caused by a missing ingredient in your diet. They thought a sickness was something you had to purge or fight off. So, they saw lemons as just a simple folk remedy. They spent decades testing these useless alternatives while thousands of sailors kept dying, all because they were looking for a complex chemical answer to a very simple food problem.

HostEventually they did settle on lemon juice, though. That's where we get the name limey for sailors, right?

GuestThat name actually comes from the mistake that caused us to lose the cure a second time. By the end of the eighteen hundreds, the Navy finally started giving sailors lemon juice, and scurvy almost vanished. But then they tried to save money by switching from Mediterranean lemons to limes from the West Indies.

GuestThere were two big problems with that move. First, those limes only have about half as much Vitamin C as lemons. Second, the ships were getting much faster because of steam engines. Sailors weren't out at sea for months at a time anymore, so they weren't away from fresh food long enough to get sick. The Navy saw that nobody was getting scurvy and thought the lime juice was doing the job. In reality, the speed of the ships was doing all the heavy lifting. They had no idea their cure had become totally useless.

HostSo they thought they had it under control, but they were just lucky because the trips were shorter.

GuestRight, and the luck ran out when they went to the Arctic. Explorers like Sir George Nares would take their teams into the ice and get stuck for months or even years. They were far away from any fresh meat and they were relying on that low-strength lime juice. Scurvy came back with a vengeance. But because they believed the lime juice was a proven cure, they assumed it couldn't be a lack of fruit causing the problem.

GuestScientists started looking for other things to blame. They wrongly thought the sailors were getting sick from a type of food poisoning in their tinned meat, or even just from a lack of exercise. They went back to square one, coming up with all these complicated theories while the answer was still just a simple molecule. It wasn't until nineteen thirty-two that Vitamin C was finally isolated in a lab. That was the moment we finally proved it wasn't about acidity or hygiene, but a specific tiny nutrient that humans simply can't build inside our own bodies.

HostIt's a bit unsettling to realize that for a long time, the only thing keeping those old wounds from opening up was a piece of fruit that we kept forgetting we even needed.