Scurvy fever, convulsions, and eventual death are frequently seen. Scurvy, including subclinical scurvy, is caused by a deficiency of dietary vitamin C since humans are unable to metabolically make this chemical. Provided diet contains sufficient vitamin C, the lack of working GULO enzyme has no significance, and in modern Western societies, scurvy is rarely present in adults, although infants and elderly people are affected. Virtually all commercially available baby formulas contain added vitamin C, preventing infantile scurvy. Human breast milk contains sufficient vitamin C, if the mother has an adequate intake. Commercial milk is pasteurized, a heating process that destroys the
Scurvy lambs, chickens, and ducks, along with lemons and oranges, due to which "some of our ill were cured of scurvy". Unfortunately, these travel accounts did not stop further maritime tragedies caused by scurvy, first because of the lack of communication between travelers and those responsible for their health, and because fruits and vegetables could not be kept for long on ships. In 1536, the French explorer Jacques Cartier, exploring the St. Lawrence River, used the local natives' knowledge to save his men who were dying of scurvy. He boiled the needles of the arbor vitae tree (Eastern White Cedar) to