non-selectively binds to proteins and has been shown to inhibit enzymes including trypsin and α-amylase, thus reducing protein digestibility in animals.16,17 Phytic acid can bind protein over a wide pH range. At acidic pH (such as in the stomach) phytic acid binds to basic amino acids such as arginine, histidine and lysine, forming protein–phytate complexes. In the small intestine at a pH above the isoelectric point of proteins, phytic acid can bind protein through cations to form protein–mineral–phytate complexes.