Trace Elements in the Fetus and Young Infant

Abstract
The trace elements are so called because they constitute less than 0.01% of the weight of the human body; however, despite their relative scarcity, their atoms are present in large numbers and each is believed to play an important role in human growth and development. For example, chromium is perhaps one of the least abundant trace elements in the body and yet even a single hepatocyte contains about 4.5 million atoms of this element. The name "trace element" is, of course, quite arbitrary and survives from the time when early investigators were experiencing great difficulties in measuring these substances; the introduction of more sophisticated techniques has resulted in an enormous increase in our understanding of the role these elements play in metabolism. This review deals with zinc, copper, manganese, selenium, and chromium. The amount of space devoted to each element is not intended to correspond to its importance in metabolism,