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 D deficiency outcome for some cancers, but evidence is insufficient to recommend that vitamin D be prescribed for people with cancer. Taking vitamin D supplements has no significant effect on cancer risk. Vitamin D, however, appears to decrease the risk of death from cancer but concerns with the quality of the data exist. Vitamin D deficiency is thought to play a role in the pathogenesis of non-alcoholic fatty liver disease. Some studies have indicated that vitamin D deficiency may play a role in immunity. Those with vitamin D deficiency may have trouble fighting off certain types of infections. It has also been