Vitamin deficiencies are seen in the United States in the young, the elderly and chronically ill individuals. Remember that vitamins are only an enzyme; that is, they promote the conversion of one substance into a second substance in the body. If none of the first substance is in the body for conversion, the process will not occur regardless of the amount of vitamins present. A normal diet will provide all the necessary vitamins, minerals and materials for the body to maintain itself; therefore, general vitamin use is unnecessary.