It is generally accepted that the basic needs of vitamins are covered by the so-called Recommended Dietary Allowances, which were originally established mainly to prevent deficiencies. However, there is more and more scientific evidence accumulating that several vitamins have additional functions, each requiring a different, but usually higher amount than the one set for the prevention of the respective classical vitamin deficiency. Such additional functions include the radical scavenging effect of various antioxidant vitamins or the role of folate in the prevention of neural tube defects. This publication wants to substantiate the relations between the scientific evidence for selected functions and the respective vitamin intake; moreover, as some of the functions in question require several vitamins due to synergistic interactions, attention will also be paid to this aspect. Special measures could in the future contribute to lower public health costs by helping to decrease the incidence of costly chronic diseases: Guidelines advising a much higher intake of fruits and vegetables have already been established to reduce the risk for certain diseases such as some types of cancer and coronary heart disease. Covering a wide spectrum of topics, this publication will not only be of interest to nutritionists, pathophysiologists and epidemiologists, but also to Public Health authorities and food and vitamin manufacturers.