Abstract A comprehensive, authoritative report of a National Research Council subcommittee reviews current knowledge concerning selenium (Se) in nutrition for nutrition, food, and health professionals. The report focuses on the chemistry of Se and its analysis; Se distribution in soils, plants, animal feeds, human foods, and water; the Se cycle in nature; biochemical functions of Se (e.g., associations with glutathione peroxidase; nutritional and metabolic inter-associations); Se dietary forms and its absorption, transport, retention, distribution, and metabolism; Se nutritional aspects (dietary requirements and deficiencies in animals, and role in human nutrition); the toxic effects of excess Se; and the effects of high and low Se exposures in human health. A summary of the findings of this report and an extensive list of literature references cited are appended. (wz)..