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
Vitamin A Approximately 250,000–500,000 children in developing countries become blind each year owing to vitamin A deficiency, with the highest prevalence in Southeast Asia and Africa. Vitamin A deficiency is "the leading cause of preventable childhood blindness," according to UNICEF. It also increases the risk of death from common childhood conditions such as diarrhea. UNICEF regards addressing vitamin A deficiency as critical to reducing child mortality, the fourth of the United Nations' Millennium Development Goals. Vitamin A deficiency can occur as either a primary or a secondary deficiency. A primary vitamin A deficiency occurs among children and adults who do not consume