It took centuries (and vitamins) for doctors to finally stop scurvy
Vitamins were the missing link in nutritional science until the 20th century. A new book on atoms traces this knowledge gap back to the world's greatest navies and scurvy.
Adapted from the book WHAT’S GOTTEN INTO YOU by Dan Levitt. Copyright © 2023 by Dan Levitt. Courtesy of Harper, an imprint of HarperCollins Publishers.
By the late 1800s, scientists had identified four of the basic substances that make up our bodies: protein, fat, carbohydrates and minerals. These four kinds of molecules form the scientific basis of the ingredient list in the first baby food: Liebig’s Soluble Food for Babies, “the most perfect substitute for mother’s milk.” Unfortunately, no one suspected that Liebig’s list was incomplete, which would explain why babies raised solely on his formula did not thrive. It turns out that we have to eat one more type of molecule to assemble ourselves.
Unhappily, a lack of this last kind of substance was responsible for four exceptionally gruesome diseases. In the seafaring age between 1500 and 1800, scurvy killed about two million sailors, many more than the who died in battle. Throughout Asia, a pernicious disease called beriberi sporadically paralyzed and killed millions. Pellagra, memorably known for its four “D”s—dementia, dermatitis, diarrhea, and death—afflicted the poor in Europe and America, particularly many in the American South who primarily ate bacon, cornbread, and molasses. Rickets deformed the bones of the children of rich and poor alike. Growing up in Arkansas during the Great Depression, my own mother-in-law’s sisters were stricken by it. Until scientists could discover the reason for these inexplicable ailments, countless victims would suffer and die hideous deaths.
Some clues, however, had long been visible, including a particularly promising one that appeared half a century before Liebig was even born. In 1747, a 31-year-old British naval surgeon named James Lind stood one day on the rolling deck of the HMS Salisbury, a three-masted ship of war outfitted with fifty cannon. As they patrolled the Bay of Biscay, off the coast of France, Lind relished the fresh air, a welcome relief from the stagnant hold below and the vexing mystery he faced there.
It had been only eight weeks since they’d left port, and already forty of the three hundred sailors on board had contracted scurvy. The men limping to Lind’s sick bay had putrid gums and red, blue, or black spots resembling bruises on their skin. They were lethargic and losing the strength to walk. He knew that, if the disease grew too advanced, he would have to cut away their grossly swollen gums just so that they could swallow their food.
In the British navy, this was hardly unusual. Scurvy was common on longer voyages. Lind was all too aware of the single worst incident, as it had happened just seven years earlier. The navy had dispatched a squadron of eight ships under the command of Sir George Anson to attack Spanish galleons in South America. Three and a half years later, Anson returned with a treasure so vast, he needed thirty-two wagons to haul it to the Tower of London. But only about 400 of his 1,900 men returned with him. Most had died of scurvy.
It was not that the navy completely ignored the disease. The problem was, there was no agreement on how to cure it.
Yet, this knowledge had once been known, at least by some. Two hundred years before, many ship captains could have told you that scurvy breaks out on long voyages that deprive sailors of fresh fruit and vegetables. The writer Stephen Bown observes that in the seventeenth century, captains made mad dashes from port to port in an attempt to outrun the disease. It was also known that lemon juice could prevent or cure it. In his 1617 textbook, The Surgeon’s Mate, John Woodall recommended lemon juice daily. The Dutch East India Company even established plantations in the Cape of Good Hope and Mauritius to provide lemons for their crews.
Over time, unfortunately, the knowledge of lemon juice’s beneficial properties somehow vanished. The reasons were many, including simple complacency. When the incidence of scurvy grew worse again, there was resistance to citrus. Lemon juice was expensive and some shipowners suspected that merchants touted the imaginary medicinal powers of lemons just to drive up the price. At the same time, physicians were peddling a confusing variety of many other supposed cures. As author David Harvie observes, there were even “anti-fruiters,” who claimed that lemons hurt rather than helped sailors on some expeditions.
Lind had seen relatively little scurvy himself until, on their tenweek voyage the previous summer, eighty of his crew had been laid low. As he cast about for an explanation, he noted that the rainy cold weather they encountered had made it hard for the crew to dry out and fostered stale air in the hold. Lind wondered if this bad air was the culprit. He also contemplated the possibility that the lack of a proper diet was to blame. Yet that seemed unlikely. “They had been afflicted by scurvy,” he would write, “even though the captain supplied the crew with mutton-broth fowls and meat from his own table.” On Lord Anson’s ships, Lind noted, scurvy had broken out in spite of a plentiful supply of what he believed to be adequate provisions and good water.
Despite Anson’s staggering loss, the brass in the British Admiralty displayed a disastrous lack of urgency. There was a great difference of opinion about its cause. Was it overcrowding? An excess of salt? Bad air? Some believed that only sluggish and lazy sailors succumbed to it. Moreover, even if they were to accept that for some strange reason lemons helped prevent it, carrying large crates of lemons on long voyages would entail great expense and was impractical besides, because lemons and lemon juice spoil. Perhaps most important, scurvy usually passed over the officers and higher-ranking seamen. So it simply seemed more expedient to replace casualties by pressing more unwitting men into service (often through trickery or kidnapping) than it was to shoulder the burden and expense of trying to prevent the disease.
Lind, newly promoted to ship’s surgeon, was horrified by scurvy. Having a sound scientific mind, he requested permission from his captain to search for a remedy by conducting an experiment that is considered by some to be the first clinical trial in all of medicine. Lind divided twelve sailors suffering from scurvy into six pairs and lodged them in hammocks in the ship’s forehold. He doled out a different remedy to each: either cider, sulfuric acid, vinegar, seawater, or oranges and lemons. The unfortunate sixth pair received a formulation that one of Lind’s colleagues recommended: an unappetizing paste of garlic, mustard seed, dried radish root, a tree resin known as balsam of Peru, gum myrrh, and for good measure, an occasional dose of barley water with tamarind along with cream of tartar to purge the system. After a week, he ran out of fruit and had to end his trial. It was by now evident that only two of the remedies had any effect. The cider appeared to help a little bit, while, incredible as it seemed, the citrus largely cured the disease—so much so that one sailor returned to duty, and Lind put the other to work nursing his companions.
You might think that Lind would immediately jump up and down yelling “Eureka,” because he had just proven, for all time, that something in citrus fruit cured scurvy. Not a chance. The unfortunate Lind was mired up to his hips in intellectual quicksand—the confusing medical theories of his day.
Lind gave himself time to make sense of his work. He retired from the navy, earned a medical degree in Edinburgh, and established a practice as a physician. Then he settled down to review many accounts of scurvy by others, before finally and conclusively explaining it.
In 1753, six years after his landmark experiment, Lind published a 456-page opus. Although the results of his experiment may seem clear-cut, his conclusions could have been, well, more conclusive. This is the point in our story where one wants to say, “Wait, wait! Can’t you see?” After perceptively reviewing fifty-four other works on scurvy, he only gets around to his own trial a third of the way through the book—and devotes just five paragraphs to it. He was confident he had shown that citrus could cure scurvy, yet he struggled to explain the malady’s cause. Concepts of disease at the time were a complete mess.
They were dominated by Galen’s idea that sickness resulted from an imbalance of bodily humors. So Lind concluded that on ships, a combination of poor diet and moist cold air blocked perspiration, and this trapped putrid unwholesome humors inside the body. He explained that citrus could open up the skin’s pores, but in a later edition he conceded that other medicines could also do the same. “I do not mean to say,” he opined, “that lemon juice and wine are the only remedy for the scurvy. This disease, like many others, may be cured by Medicines of very different and opposite qualities to each other, and to that of lemons.” As the author Frances Frankenburg observed, “If there was ever a researcher who doubted his own findings, it was James Lind.”
On the bright side, Lind did recommend that sailors use lemon juice to prevent the disease. But he followed that sound suggestion with an uncharacteristically sloppy error. To prevent the juice from rotting, he suggested it should be heated to make a syrup—little suspecting that heat destroys the juice’s curative powers. To add to the confusion, many distinguished physicians championed other cures that were entirely ineffective. One sea surgeon wrote sourly, “Dr. Lind reckons the want of fresh vegetables and greens a very powerful cause of the Scurvy; he might with equal reason, have added fresh animal food, wine, punch, spruce beer, or whatever else is capable of preventing this disease.” Lind’s critic went on to recommend rice as a remedy, or a mixture of one-fourth brandy and three-fourths water. Scurvy rampaged on, unabated.
In 1756, three years after Lind published his treatise, the Seven Years’ War broke out between Britain and France. Of the 184,899 sailors who enlisted or were pressed into the Royal Navy, only 1,512 were killed in action. Another 133,708 expired from disease—primarily scurvy. Scurvy continued to hamstring the British navy during the American Revolution that followed soon after. If the Admiralty had provided lemons to their crews, some argue, the British might have prevailed against the colonies, or at least held off France’s navy and negotiated a more favorable settlement.
It wasn’t until 1795, a year after Lind’s death, that the Royal Navy began issuing lemon juice to sailors. For a time, scurvy actually ceased to be a problem. But after taking one fruitful step forward, the navy leaped two steps back. Eighty years later, they switched to limes, which they could buy more cheaply from plantations in the British West Indies. Henceforth, British sailors were, of course, known as limeys. But regrettably, limes were much less effective at preventing scurvy, and this cast doubt on the value of any citrus juice as a cure. Even in the early twentieth century, when doctors agreed that fresh fruit and vegetables could treat scurvy, they still could not agree on the disease’s cause, which is why, in 1912, scurvy plagued the British explorer Robert Scott’s meticulously planned expedition to the South Pole. His conviction that bacterial food poisoning was to blame likely hastened his own demise. After hundreds of years, scurvy’s cause still remained a mystery.