Once thrown away, disposable items such as diapers and sanitary pads can take hundreds of years to decompose, because their absorbent parts and waterproof layers contain plastics and other synthetic polymers. But now, researchers are replacing these materials with porous components made from protein biomass that is often discarded by the food and agricultural industries. These components are sustainable and biodegradable, and could potentially allow future diapers and sanitary pads to be flushed down a toilet or used as fertilizer.