Now uncommon in the U.S., scurvy was a common affliction for sailors during the age of exploration
By Eva Briggs, MD
I’m halfway through reading a long but fascinating history book, “Over the Edge of the World” by Laurence Bergreen.
I’ve never been much of a history buff thanks to a scary fourth-grade teacher who managed to make history as dull as possible. But this book about Magellan’s voyage to circumnavigate the globe is meticulously researched and describes events of 500 years ago in captivating detail. The author provides a lengthy description of the disease scurvy, a common affliction for sailors during the age of exploration.
Scurvy is caused by vitamin C deficiency. Most mammals are able to synthesize vitamin C in their livers. Humans and a few other mammals (higher primates, guinea pigs, capybaras and fruit-eating bats) lack a necessary enzyme and can’t make vitamin C. They must obtain it from their diet. The best sources are fruits and vegetables, such as citrus fruits, red and green peppers, kiwis, strawberries and broccoli. Vitamin C is added to fortified breakfast cereals. Cooking can destroy vitamin C. Fortunately, many foods high in vitamin C are eaten raw. Microwaving and steaming produce less loss of vitamin C than other cooking methods.
Over 500 years ago, people did not know about vitamin C. Sailors embarking on long voyages couldn’t take fruits and vegetables, as they would spoil during months at sea. It takes about a month without vitamin C to start scurvy symptoms. People then attributed the symptoms to miasmas, a noxious form of bad air. Arab sailors didn’t understand vitamin C, but they did understand that including fresh fruits and vegetables in their diet would prevent scurvy. The Europeans didn’t recognize this.
Vitamin C is essential for the body to synthesize various substances, including collagen. Collagen acts like a framework or support for various tissues. Many of the symptoms of scurvy arise from the inability to make or repair collagen.
The disease starts with fatigue and malaise. Bone pain and muscle aches soon follow. The skin becomes rough with easy bruising and petechiae (little red dots caused by bleeding from damaged capillaries). Wounds heal poorly. Gums swell and bleed and teeth fall out. As the disease progresses, patients develop jaundice, fluid retention, nerve damage, fever and convulsions. Untreated scurvy leads to death.
Treatment with vitamin C, in doses as low as 10 mg per day, leads to rapid recovery within a few weeks.
As an aside, excessive doses of vitamin C are dangerous. The recommended daily allowance is 75-90 mg per day, or up to 120 mg/day in pregnant women. The body doesn’t store excess vitamin C but excretes the extra vitamin C in the urine. Megadoses exceeding 2,000 mg per day overwhelm the kidney’s ability to get rid of the excess. When that happens, vitamin C leads to the formation of oxalate stones. This can produce renal failure or in the worst case, death.
Fortunately, vitamin C deficiency and scurvy are uncommon in the U.S. currently. Those at risk are neglected children, people with unusual eating habits, those with alcoholism and older people who live alone.
Back to Magellan in 1520. He started the voyage with a crew of about 270. Records document that at least 19 men died of scurvy, but the death toll from scurvy might have been as many as 69.
Eva Briggs is a retired medical doctor who practiced in Central New York for several decades. She lives in Marcellus.