myo-Inositol(1,2,3,4,5,6)hexakisphosphate (InsP(6) or 'phytic acid') was first known as the storage form of phosphorus in seeds. Seed-derived dietary InsP(6) can contribute to iron and zinc deficiency in human populations. Excretion of 'phytic acid phosphorus' by non-ruminants such as poultry, swine and fish can contribute to water pollution. Sustainable solutions to these important problems might depend on progress in the molecular biology and genetics of InsP(6) accumulation during seed development. The development of 'low phytate' grain and legume genotypes could help advance our understanding of this biology, and when used in foods and feeds might help to reduce human malnutrition and reduce animal waste phosphorus.