Vitamins: the tortuous path from needs to fantasies.
The discovery of vitamins in the early 1900s, their chemical characterization and the clarification of their metabolic functions are sequential aspects of a brilliant chapter in the history of modern nutritional science. Despite our current knowledge about vitamins, inadequate vitamin status still abounds in the less industrialized world. With some vitamins, toxicity also poses a problem. The average daily amounts of dietary vitamins needed to maintain physiological functions in generally healthy persons is fairly well known. Nonetheless, new indicators of vitamin status and in vivo kinetic analysis should allow refinement of these values. The dietary intake of fruits and vegetables has been associated with a decreased risk of major chronic diseases, including cancer and cardiovascular diseases. The specific contributions of different components of the diet, including several vitamins, to this apparent protective effect is still uncertain. Factors besides diet that affect chronic diseases are lifestyle, genetics, medical awareness, and habits like smoking. Fantasies among generally healthy persons that large supplements of any single vitamin or combination of them, like some magical amulet, will significantly stave off ill health have captivated a sizable percentage of our population. Such beliefs can only be changed, if at all, by appropriate educational messages based on convincing scientific data.
Olson
J A
JA
Department of Biochemistry & Biophysics, Iowa State University, Ames 50011.
D002908:Chronic Disease; D006801:Humans; D009751:Nutritional Requirements; D009752:Nutritional Status; D014815:Vitamins / Q000008:administration & dosage*
D014815:Vitamins