Vitamin needs of the elderly.

Vitamin deficiency is a result of gradual depletion of body stores secondary to poor dietary habits or to disease. Marginal or preclinical vitamin deficiency results in nonspecific symptoms such as malaise, irritability or somnolence, loss of appetite and weight, and impairment of psychologic and physical performance socially or at work. These signs precede clinical signs of disease. The elderly are particularly vulnerable to vitamin deficiency because of the high incidence of illness and disability in the later years of life and because of other common problems, such as low income, poor appetite, and social isolation.