Adverse Effects of Overdosage of Vitamins and Minerals
Lewis A. Barness MD1
1 Professor and Chairman, Department of Pediatrics, University of South Florida College of Medicine, 12901 N 30th St, Tampa, FL 33612
Throughout almost three centuries, knowledge of the uses, needs, and metabolism of trace nutrients, vitamins and minerals, has been acquired. This knowledge can be divided into five phases.
The first phase occurred during a period of about 200 years and was one mainly of discovery. Animals and/or humans were noted to have diseases that were related to deficiencies. Thus, in 1753 a Scottish surgeon in the British navy showed that citrus fruit could prevent or cure scurvy, and about 200 years later ascorbic acid was isolated, synthesized, and used. Many of the trace elements were determined either to correct deficiencies or to be growth factors for animals. Discovery of knowledge continues but at a less rapid rate.
The second phase, which considerably overlaps with the first, is related to determination of the mechanism of action. This required, first, study of animals, then, tissues, and, now, cells and cell components. Many biochemical pathways have been determined, and many vitamins and minerals have been identified as part of enzyme systems. Still others are to be explored and determined.
The last three phases appeared irregularly but periodically, two with scientific input and one by hope, prayer, and deductin.1
The third phase was one of the determination of recommended daily requirements and allowances (RDA).
