Bioavailability of essential and toxic trace elements. Introduction
O'Dell, B.L.
Federation Proceedings 42(6): 1714-1715
1983
ISSN/ISBN: 0014-9446 PMID: 6832392 Document Number: 197099
Introductory overview remarks are presented for a symposium of 5 papers on the bioavailability of trace elements. Intrinsic (or physiologic) and extrinsic (or dietary) factors affecting bioavailability, and factors affecting the assessment of bioavailability, are briefly highlighted and discussed. Intrinsic (physiological) factors include: species and genotype; age; sex; metabolic function; nutritional status; physiological stress; and intestinal microflora. Dietary or extrinsic factors affecting bioavailability include: the solubility of the particular element species; absorption of diet components on large surfaces (e.g., fiber, silica); the oxidation state of the element; the competitive antagonism between and among element ions; and positive or negative chelation of trace elements with natural chelating agents in foods (e.g., phytate). The latter 2 factors are specifically addressed with repect to trace element bioavailability. (wz)