MINERAL CONTENTS OF BRANS PASSED THROUGH THE HUMAN GI TRACT

Concentrations of Cu, Fe, Zn, Ca and phytate were measured in dry-milled corn bran, wheat brans and soybean hulls prior to being baked in bread and after passage through the human GI [gastrointestinal] tract. Cu, Fe, and Zn increased by factors of from 2 to 4 and Ca increased at least 10-fold in dry-milled corn bran; Ca increased and phytate decreased in wheat brans; Zn increased and Fe decreased in soy hulls. Indigestible remnants of wheat brans in the human colon associate preferentially with Ca and dry milled corn bran remnants can be loaded with increased concentrations of all 4 minerals, and especially with Ca. Concentrations of minerals and phytate were significantly greater in whole fecal samples from wheat bran diets than in the corresponding retrieved bran remnants.