- The record for vitamin C levels is brilliantly held by the amla fruit, or Nepalese gooseberry, with 610 milligrams of vitamin C per 100 grams. The guava, with 228 mg per 100 g, comes in at an honourable second.
What if "Saint Louis" had not died of the plague or dysentery, as previously thought, but of particularly severe scurvy after months on a diet that no one would recommend? That, at any rate, is the thesis of forensic pathologist Philippe Charlier, based on an analysis of the toothless lower jaw of Louis IX, piously preserved in the shelter of Notre-Dame de Paris since it was repatriated from Carthage, where the sovereign died during the Eighth Crusade. Joinville, a faithful companion of the king, described the symptoms in his memoirs: "The skin of our legs was covered with black and earthy stains like an old shoe, their flesh was drying out while that of our gums was rotting...".
Anecdotal evidence? Yes and no. Charlier's work confirms once again that scurvy did not suddenly appear in modern times, even if doctors in Antiquity or the Middle Ages did not put a name or a precise diagnosis to a pathology whose most characteristic symptoms - loose teeth, purulent gums, oedemas, skin haemorrhages and so on - can evoke other diseases. After all, gingivitis and alitosis are not specific to scurvy.
So why do we almost instinctively associate scurvy with the age of sailing and exploration? Because it found a marvellous opportunity to kill as many people as possible. If it weren't for the remarkable advances in maritime science at the end of the Middle Ages, scurvy would not occupy its rightful place in the collective imagination, rich in toothless pirates and amorphous sailors, exhausted by the disease that gnaws at them, sadly spitting out a molar from time to time over the rail.
When Christopher Columbus and his cronies began to criss-cross the world, the ships they used were little jewels of naval technology, capable of carrying everything they needed to last weeks or even months at sea before calling in somewhere to find the fresh food they didn't yet know how to keep on board. A case in point? While Christopher Columbus took just five weeks to reach North America, Vasco da Gama took eleven months to reach the East Indies after setting sail from Lisbon in July 1497.
And that's a real problem insofar as scurvy is precisely the painful consequence of a deficiency in vitamin C, an acid that wasn't discovered until 1932 and is found in fruit and vegetables - oranges, lemons, turnips and Brussels sprouts, to name a few. And the problem with a vitamin C deficiency is that the substance is essential to the body: it enables collagen to maintain its structure, and so prevents tissues such as blood vessels from going haywire after a few weeks, when the body starts to seriously crave it.
For most mammals, this is not problem: their bodies secrete collagen naturally. For primates in general, and humans in particular, tough luck: a clever evolutionary trick means that this is not the case. So they have to compensate by finding vitamin C where it's found, in meat, fruit, vegetables, or plants like parsley. And even then, you´ll get your proper dose as long as you don't cook these but eat them as they are, or almost as they are. It turns out, vitamin C is very shy and decomposes as soon as it is exposed to air, heat or light.
A daily meal on board a 16th century caravel or an 18th century ship, was not particularly good. The average diet was a sort of nutritionist's nightmare: biscuits, dried or salted meat (cooked and re-cooked), flour cakes, more or less drinkable water, beer and other spirits.
In short, there's no vitamin C in sight. And that has some pretty tough consequences, perfectly described in the logbooks of captains who knew full well what to expect, but did not have the slightest clue as to why their crew suddenly started developing symptoms, each more painful than the last: intense fatigue, gingivitis, loosing teeth, oedema, muscle and joint pain, skin rashes, paleness, and bleeding from the nose, genitals or eyes.
The decline was slow but painful, until the "plague of the seas" finally got the better of the sailors, either through exhaustion or as a result of an infectious disease that the body was unable to fight. This led to a particularly ugly death, which does nothing to boost the morale amongst seafarers.
It's impossible to put a figure on the number of sailors who died of scurvy, but it was in the tens of thousands - a million between 1600 and 1800 according to English historian R.E. Hughes. To be honest, this wasn't necessarily a big problem for shipowners: most of the time, finding sailors wasn't difficult, and it was enough to set sail with an overstaffed crew to get by, or at least to manoeuvre ship and operations despite the losses. Pragmatic indeed.
With such a mindset, the issue of scurvy prevention, (a term which of probably Icelandic origin, from the Norse skyrbjug) remained unanswered for a long time. Even if the sailors of the time quickly realised that their health improved radically when they stopped over in lands where they could buy fresh produce. They lacked theory, but empirical observation alone was enough - which did nothing to change the problem: how could fresh food be transported without it rotting at sea after a few days?
Finding the answer took its time, even if a few visionaries spotted the solution early on, such as the French apothecary François Martin, who wrote in 1604 in his Description du premier voyage fait aux Indes orientales (Description of the first voyage to the East Indies), that "there is nothing better for preserving oneself from this disease than to often take lemon or orange juice, or to often eat fruit, or else to stock up on syrups of lime, sorrel, barberry or a herb called coclearia, which seems to contain the real antidote, and to use it often". Or like the head of the English East India Company's medical staff, John Woodall. In 1617, he recommended that men should consume citrus fruits to protect themselves from scurvy, a salutary piece of advice that everyone was banging on about for the excellent reason that nobody knew how it worked.
The issue remained pretty much unchanged for another century, before another English doctor made a sudden breakthrough in science and clinical studies in 1742. That year, England was at war with Spain, and found itself ridiculed when one of its ships, the HMS Gloucester, had to be abandoned at sea by what was left of the crew for lack of able-bodied men to manoeuvre it.
This was beginning to take its toll, and the Royal Navy decided to take a serious look at the issue of scurvy. And the Royal Navy was in luck, because it had James Lind in its ranks, a Scotsman who had read the writings of his colleague John Woodall. Lind would go down in history as the first doctor to have conducted a clinical study, in which he divided his twelve patients into two groups. The first was given vinegar, garlic juice, cider or seawater. The second group was given orange and lemon juice - which, by the way, must be very pleasant to sip when your gums are on fire, but it worked beyond all expectations. In less than a week, the six crewmen saw their condition seriously improve, while the others' health continued to deteriorate.
Citrus fruits was found to help fight scurvy: Lind 1 - Scurvy 0. You'd think that with such a clear demonstration, the case would be made - but not really. Lind grasped the principle but lacked the resources to understand the mechanisms at work. Using the theory of humours (or "humorism"), he concluded that the dry, acidic mood had to be influenced to restore the balance with the wet mood, which was bound to be reinforced on board ship. He therefore recommended the consumption of hydrochloric acid, mixed with drinking water rations or malt wort. And that's how you ended up drinking a perfectly ineffective beverage, for the simple reason that there wasn't a single milligram of vitamin C in it. It wasn't until 1799 that the Royal Navy stuck to good old lemon juice, or rather lemon rob, which added a touch of alcohol - a military secret that became widespread on its ships from the beginning of the 19th century, and was more or less copied by the fleets of other maritime nations.
Over time, the British navy began to replace its lemon juice with lime juice, imported by the shipload from its Indian colonies. And that sounds great on paper: lime juice is much more acidic to the taste than yellow lemon. Except that lime is much less rich in vitamin C than the other. The remedy was still effective - but much less so. Nobody realised this however thanks to the development of steam-powered shipping, which shortens journey times. Apart from the crews of whalers, who were often off on ocean voyages lasting one, two or three years, the replacement of lemon juice by lime juice had no visible consequences at sea for shorter journeys, especially as the discovery of canned food in 1804 also did its part to improve the diet of sailors. On the other hand, this omission would cause some serious damage in certain cases, for example during polar expeditions.
However, from the mid-19th century onwards, the major scurvy epidemics occurred mainly on land: the great Irish famine of 1845 to 1852 caused a total of over a million deaths, many of them from scurvy: the potato crops, which were low in vitamin C but abundant, had been ravaged by mildew. Scurvy epidemics occurred again from time to time, during the California Gold Rush (1848-1856, with 10,000 deaths), the American Civil War (during 1861-65) and the Siege of Paris in 1870. Yet the figures do not come close to the many years in which scurvy was a death sentence for those at sea. In any case, as soon as the supply channels were re-established in the epidemics mentioned before, vitamin C deficiencies were more or less eliminated naturally.
More insight would arrive thanks to the work of two Norwegian researchers, Axel Holst and Theodor Frølich. They were working on beriberi in 1907, with a guinea pig model. This is one of the few mammals, apart from primates, not capable of producing ascorbic acid on its own. This meant that by trying to give them beriberi, the two researchers gave them scurvy. A real stroke of luck, since their discovery highlighted the role of dietary deficiencies in the development of the disease.
To finally understand how scurvy 'works', however, we had to wait until 1932 and the discovery of vitamin C by the Hungarian scientist Albert Szent-Györgyi, who finally, managed to isolated ascorbic acid.