Scurvy is a disease caused by a dietary deficiency of vitamin C (ascorbic acid). The disease has occurred with regular frequency throughout human history and prehistory in populations lacking fresh foods, especially vegetables and meat. Deficiency in vitamin C may accompany wars and famine, but it is most commonly associated with post-Renaissance European exploration, particularly ocean voyages.

Vitamin C was first isolated in 1928 by the Hungarian scientist Albert Szent-Györgyi, and synthesized by a Swiss group in 1933. It is important in maintaining the healthy condition of the body's mesenchyma, specifically connective tissues (which bind together and support body structures), osteoid (the organic part of bone) and dentin (the bone-like portion of teeth). Deficiency of the vitamin causes a breakdown in the binding function of these tissues, producing a series of characteristic signs and symptoms: weakness, lethargy, irritability, anemia, purple spongy gums which bleed freely, loosening teeth, the reopening of healed scars (including refracturing of bone) and hemorrhaging in the mucous membranes and skin. In severe cases the mortality rate is high.

Scurvy was a serious problem throughout the whole period of exploration and settlement in Canada. In 1535 Jacques Cartier's voyage to the New World brought him to the present location of Québec City (Stadacona) where he and his men spent the winter. Signs of scurvy soon appeared among the crew. By Feb 1536 only 10 of the 110 men on the expedition were in good health. Also, Cartier noted that many people in the local native population succumbed to the disease before the end of 1535. Many of Cartier's men were saved by drinking a native concoction of ground coniferous needles and bark (called "anneda," probably white cedar) boiled in water. In 1542 a party of 200 French under Roberval wintered near Cartier's earlier camp. During that winter about 50 died of the disease, and it appears they did not employ the cure that had saved Cartier's men. Subsequent explorations and settlements in the New World met regularly with the catastrophic effects of scurvy during long and cold winters and food shortages.

During the 18th century scurvy caused more losses in the British navy than were suffered in enemy action. A surgeon with the Royal Navy, James Lind, conducted an extensive controlled experiment on the effects of diet on sailors with scurvy, and the results were published in 1753 in the landmark book A Treatise of the Scurvy. Lind recommended the use of citrus fruits in treating and preventing scurvy during ocean voyages, advice which was not heeded by the Royal Navy until 1795.

Scurvy was a major problem on nearly all of the 19th-century polar expeditions, and the tragic loss of John Franklin's third arctic expedition in 1847 has been partly attributed to the disease. Though foods known to be antiscorbutic (anti-scurvy) were carried by these expeditions, the effectiveness diminished over a period of months as the vitamin C oxidized, leaving the explorers without protection. Many armies during WWI also suffered very severe outbreaks; by WWII the problem of scurvy was monitored closely and all but eliminated. In Canada the years 1945-65 were marked by outbreaks of scurvy in bottle-fed infants given evaporated milk (then lacking in vitamin C).

Today scurvy is rare and is usually related to poor attention to diet, or to diets heavily weighted towards a single food low in vitamin C.