Tuesday, October 6, 2015

How the Cure for Scurvy was Lost

In the 1700s, British Royal Navy worked out how to prevent scurvy, which had been a terrible scourge of men on long sea voyages:
The scheduled allowance for the sailors in the Navy was fixed at 1 oz. lemon juice with 1 + oz. sugar, served daily after 2 weeks at sea, the lemon juice being often called ‘lime juice’ and our sailors ‘lime juicers’. The consequences of this new regulation were startling and by the beginning of the nineteenth century scurvy may be said to have vanished from the British navy. In 1780, the admissions of scurvy cases to the Naval Hospital at Haslar were 1457; in the years from 1806 to 1810, they were two.
In 1810, the Royal Navy understood perfectly well how to treat scurvy. So Maciej Cegłowski of Idle Words was shocked to discover, from reading Apsley Cherry-Garrard's account of Scott's disastrous journey to the South Pole, that by 1911 this knowledge had been lost. Here is Cherry-Garrard's account of a lecture given to the expedition by one of its Royal Navy doctors:
Atkinson inclined to Almroth Wright’s theory that scurvy is due to an acid intoxication of the blood caused by bacteria. . . . There was little scurvy in Nelson’s days; but the reason is not clear, since, according to modern research, lime-juice only helps to prevent it. We had, at Cape Evans, a salt of sodium to be used to alkalize the blood as an experiment, if necessity arose. Darkness, cold, and hard work are in Atkinson’s opinion important causes of scurvy.
Amazing. The leaders of what was supposed to be a scientific expedition in 1911 knew less about one of exploration's greatest curses than ordinary sailors of the Napoleonic era. Cegłowski goes on to explain in a convincing way how this happened.

Part of the trouble has to do with confusing lemons and limes; most people used the words interchangeably. The British Navy of 1800 used lemon juice, mainly from Sicily. In the 1860s they switched to lime juice from British colonies in the Caribbean. Lime juice actually has much less Vitamin C than lemon juice. Plus, the amount of usable Vitamin C declines as the juice is stored, and the lime juice the were using was often pretty old. So in the 1870s the lime juice being given to sailors had little protective value against scurvy.

But that didn't matter, because pretty much all fresh food contains Vitamin C, and the diet of sailors in the 1870s included enough fresh meat and vegetables that they got sufficient Vitamin C for their needs. They therefore didn't notice that the lime juice wasn't working. Based on Dr. Atkinson's lecture, it seems that somebody studied Navy-issue lime juice some time before 1911 and discovered that it had little effect on scurvy. From this doctors drew the incorrect conclusion that the whole citrus juice cure was a mistake and embarked on wild theories about acid in the blood. Not until 1932 was Vitamin C isolated and the actual nature of the disease and the cure finally explained.

It is a remarkable story of forgetting, with grim consequences for Scott's men.

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