Why was the cure for scurvy found, then forgotten?

Scurvy was shown to respond to citrus in 1747, but nobody could explain why, so the finding never settled into firm practice. Delays in adopting it, treatment of the juice that destroyed its value, a cheaper but weaker fruit, and a later theory that blamed bacteria all pushed the knowledge aside. The real cause, a vitamin C deficiency, was not identified until the early twentieth century. [1] [2]

James Lind, a naval surgeon, compared six treatments on twelve sailors with scurvy, giving two men each a different remedy, including cider, dilute sulfuric acid, vinegar, sea water, and oranges with a lemon. The citrus ran out after about six days. Lind published the account in his 1753 treatise, but it occupied only a few pages of a roughly 450-page book. Several printings and translations had no immediate effect on the Royal Navy, according to the [ccjm.org](https://www.ccjm.org/content/87/8/453) account. [2]

Lind himself seemed unsure of his result. Working within the old theory of imbalanced bodily humors, he blamed poor diet and moist air that blocked perspiration, and he later conceded that very different medicines might also cure the disease. [popsci.com](https://www.popsci.com/health/whats-gotten-into-you-dan-levitt/) quotes one author as saying that if there was ever a researcher who doubted his own findings, it was Lind. [3]

The Admiralty saw no consensus on the cause: overcrowding, salt, and bad air were all proposed. Lemons were expensive and spoiled, and scurvy mostly spared officers, so replacing dead sailors seemed easier than preventing the disease. Some shipowners suspected merchants of exaggerating lemons' powers to raise prices, and there were also physicians who promoted many other cures. The Navy began issuing lemon juice only in 1795, a year after Lind died, and for a time scurvy stopped being a problem. [3] [4]

Lind suggested boiling the juice into a syrup, but heat destroys vitamin C, so the preserved product was useless. Later the Navy switched from lemons to limes, which were cheaper from the British West Indies. Limes contain less vitamin C, and the change was made partly because acidity was popularly assumed to be what mattered, even though Lind had noted that acids alone did not work. Juice exposed to air or copper piping lost further potency. [5] [1] [3]

Two further developments muddied matters. Fresh meat was found to cure scurvy too, which encouraged the idea that tainted meat and bacteria were responsible. Meanwhile steam ships shortened voyages, so scurvy appeared less often and the weaker limes seemed to work well enough. By Scott's 1911 expedition, a surgeon wrote that the reason for little scurvy in Nelson's day was unclear, and Scott's belief in food poisoning likely contributed to his own demise, according to the popsci.com account. [1] [3]

In 1907 Axel Holst and Theodor Frølich, studying beriberi, used an animal model to show that scurvy could be prevented with lemon juice, as Lind had shown over a century and a half earlier. Albert Szent-Györgyi later used that model and discovered vitamin C in 1930, winning a Nobel Prize. [1]