Scurvy, now known to be caused by a lack of vitamin C, is one of the world's oldest and most devastating deficiency diseases. Historians have been describing scurvy since ancient times primarily because the disease so often seemed to attack invading armies, sailors on long sea voyages, explorers, and even crusaders. For example, it was scurvy, rather than savage storms or hostile natives, that killed many of the crewmen who sailed with Vasco da Gama (1469-1524) in 1498 and with Ferdinand Magellan (1480-1521) in 1519.

Scurvy begins innocently enough, usually with mild fatigue, bleeding gums, and hemorrhagic bruises on the skin. However, after several months of a diet lacking any vegetables or fruits, worsening physical condition continues, resulting in weakened bones, loose teeth which ultimately fall out, severe joint pain, profuse bleeding from a simple cut, anemia, and eventually death.

Fortunately for later researchers, folk remedies for scurvy occasionally appeared...