Phytate content of foods: effect on dietary zinc bioavailability
Oberleas, D.; Harland, B.F.
Journal of the American Dietetic Association 79(4): 433-436
1981
ISSN/ISBN: 0002-8223 PMID: 7288050 Document Number: 177703
Naturally occurring phytate--an organic compound found in grains, legumes, fruits, and vegetables--binds zinc (and other minerals), causing it to be excreted from the body and thus making it unavailable for zinc nutriture. The phytate and zinc content of selected foods is listed and phytate:zinc molar ratios are calculated from the data. Phytate:zinc molar ratios of vegetarian and non-vegetarian menus are analyzed. These ratios provide an estimate of the bioavailability of daily zinc intakes, and can therefore be used to evaluate risks of zinc inadequacy. A daily phytate:zinc molar ratio of 10 or less represents acceptable dietary zinc intake. Although other factors influence zinc nutriture, the ratio concept is a useful tool for the assessment of zinc status. (author/nm)