Ascorbate and citrate extracted more iron than EDTA from pig foodstuffs (P less than 0.001). Glucose-saline solution (GSS) and ascorbate were less capable than citrate of extracting iron from maize tortilla (P less than 0.001). GSS extracted 16-32% of the whole iron contained in the studied foodstuffs; 30, 40 and 42% of the remaining iron in maize bran, wheat bran and pig feed was released with 0.1 M HCl. 40% of the remaining iron in pig's feed was released with 5% pepsin-0.1 M HCl while the iron of cereals required an additional extraction with 1% ascorbate. 5% pepsin-0.1 M HCl solutions released more iron as the protein content in the foodstuffs increased (P less than 0.001). Iron-extracted maize fibers (Ftw/Fe) bound significantly more iron than Ftc/Fe, FDA and FDN correspondingly (P less than 0.001). Phenytoin bound significantly more iron than total maize fibers both, with and without previous iron extraction (P less than 0.001). Also, phenytoin combined with maize-fiber bound less iron than phenytoin alone in G.S.A.