What scurvy is
Scurvy is a disease caused by a long-term shortage of vitamin C, which the body needs to make collagen and to maintain blood vessels, skin and connective tissue. Humans cannot make vitamin C themselves, so it has to come from food, especially fresh fruit and vegetables. Stored food, such as the salt meat and biscuit that formed much of a sailor’s diet, contained very little.
The symptoms developed slowly, often after weeks or months without fresh food. Early signs were weakness, tiredness and aching joints. Later came swollen and bleeding gums, loosened teeth, bruising, and old wounds that reopened. Without treatment the illness could be fatal. Because it appeared gradually on long passages, it was easy to confuse with other ailments.
A disease of long voyages
Scurvy is old, but it became a defining problem of sea travel once ships began to spend months out of reach of fresh supplies. During the age of exploration, long passages around Africa and across oceans brought it to prominence. Accounts of early voyages, including those to India around the Cape route, report heavy losses among crews, although exact numbers are uncertain and often come from writers with limited records.
In some cases, scurvy killed more sailors than battle or storm. The best-known example of such losses is Commodore George Anson’s circumnavigation of 1740 to 1744, in which the great majority of the men who died are generally attributed to disease, with scurvy as a major cause. The expedition left with several ships and returned with only one, and the number of deaths was a shock to the public and the navy.
What people thought caused it
For centuries, no one knew the real cause. Theories pointed to bad air, damp, laziness, the salty diet or an imbalance of the body’s humours. Remedies were equally varied, from vinegar and malt to exercise, fresh air, and a range of medicines. Some of these treatments had no effect, while a few, by accident, included some vitamin C.
Yet there was also a body of practical experience suggesting that fresh fruit helped. As early as the 1590s, the English commander Richard Hawkins wrote that oranges and lemons were effective against the disease. In 1601, an East India Company expedition under James Lancaster reportedly gave lemon juice to the crew of one ship, and that crew suffered less than those on the other ships. These accounts did not lead to general adoption, partly because they were not systematic and partly because competing theories remained popular.
James Lind’s trial
The Scottish naval surgeon James Lind is the figure most often linked with the cure. In 1747, aboard HMS Salisbury, he divided twelve sailors with scurvy into six pairs and gave each pair a different treatment. The treatments included cider, diluted sulphuric acid, vinegar, seawater, a mixture of herbs and spices, and two oranges and a lemon each day. The pair that received the citrus improved dramatically, and one was able to return to duty and help care for the others.
Lind published his results in A Treatise of the Scurvy in 1753. It is often called an early example of a controlled clinical trial, though it was small, and Lind himself did not fully accept that citrus was the single answer. He also recommended other remedies and suggested concentrated preparations of juice that, once boiled down, lost much of their potency. As a result, the clarity of the experiment did not translate immediately into a clear policy.
Captains, experiments and slow change
During the later eighteenth century, some commanders adopted anti-scorbutic measures. Captain James Cook, on his Pacific voyages, paid close attention to diet and hygiene, taking on fresh food when possible and carrying items such as sauerkraut and malt. His first voyage, from 1768 to 1771, is noted for the small number of deaths from scurvy, and the Royal Society recognised his methods. Historians debate which measures were most effective, because Cook’s regimen mixed many elements, and some of them had little antiscorbutic value.
Other medical writers, notably Gilbert Blane and Thomas Trotter, pressed for the use of lemon juice in the navy. Lemon juice was issued as a regular ration in the Royal Navy from 1795, and scurvy dropped sharply in the fleet in the following years. The decision is often credited with improving the health and endurance of crews during the long wars with France, including the blockades that kept ships at sea for months.
Limes, setbacks and understanding
Later in the nineteenth century, the navy and merchant fleets shifted from lemons to limes, which were cheaper and available from British colonies in the West Indies. West Indian limes contained less vitamin C than the Mediterranean lemons used earlier, and juice stored for long periods lost more of its strength. The change may have reduced the effectiveness of the ration. The practice also gave rise to the nickname “limey” for British sailors.
Scurvy did not disappear completely. It appeared on expeditions in polar regions in the nineteenth and early twentieth centuries, where methods of preservation, theories about “tainted” tinned food and incomplete understanding all caused confusion. Not until the 1930s was vitamin C isolated and identified as the missing nutrient, which finally gave the old observations a clear explanation.
Why the story took so long
The history of scurvy shows how hard it can be to turn evidence into practice. Lind’s trial was suggestive, but the disease took weeks to show itself, the diets involved differed in many ways, and preservation changed the active ingredient in unseen ways. Competing theories and the cost of supplying fruit also slowed acceptance, and practical men on ships often relied on whatever had worked for them before.
The disease also shaped the history of navigation and exploration. Plans for long passages, from voyages in the Pacific to polar sea exploration, had to account for the limits of human endurance, and ship surgeons struggled with a condition they could see but not explain. The link between scurvy and shipboard provisions gradually became part of general knowledge, and with it came a better understanding of the importance of fresh food on every long voyage.