Lind Cures Scurvy with Citrus
In 1747, James Lind, a Scottish naval surgeon, carried out what is often described as one of the first controlled clinical trials in medical history. Aboard HMS Salisbury, he compared several proposed remedies for scurvy and found that oranges and lemons produced a striking recovery. The experiment pointed toward a cure for a disease that had killed more sailors than battle, shipwreck, and all other causes combined, though its full impact took decades to arrive.
Scurvy had plagued long sea voyages since the Age of Discovery. Sailors on diets of salted meat and hard biscuit developed bleeding gums, exhaustion, old wounds reopening, and eventually death. In 1740 to 1744, George Anson's circumnavigation lost the large majority of its crew, most of them to scurvy. Explanations at the time were many and contradictory, blaming bad air, idleness, damp, or poor digestion. Remedies were equally varied, and folk wisdom about fresh fruit and greens had been recorded for centuries without being widely accepted.
Lind's trial took place in May 1747. He selected twelve sailors with similar symptoms, housed them together, and gave them the same basic diet. He divided them into six pairs, each receiving a different treatment: cider, diluted sulfuric acid, vinegar, seawater, a spiced paste with other ingredients, or two oranges and a lemon daily. The pair given citrus improved dramatically, one man becoming fit for duty within about a week and the other well enough to nurse the sick. The cider group showed slight improvement, while the rest did not. The sample was tiny by modern standards, but the method of comparing treatments side by side was ahead of its time.
Lind published his findings in A Treatise of the Scurvy in 1753, yet the Royal Navy did not adopt citrus as standard issue for decades. Lind himself did not fully trust his own result, and he promoted impractical preparations such as concentrated juice boiled down, which destroyed much of its benefit. Confusion over sources and competing theories also slowed acceptance. Captain James Cook's voyages in the 1770s showed good results from a broad regimen of fresh food, and the Navy finally mandated lemon juice rations in the mid-1790s. Scurvy largely vanished from the fleet soon after.
The change strengthened British naval endurance, allowing long blockades and distant campaigns during the Napoleonic Wars. The underlying cause remained unknown until the twentieth century, when vitamin C was identified as the missing nutrient. Lind's legacy lies both in the cure and in his example of testing medical claims through comparison rather than authority.