Some embodiments relate to metal binding agents and chelators for preparing food products (including nutritional supplements) from vegetable and plant sources for the reduction of heavy metal content. In some embodiments, the plant sources include rice. In some embodiments, when bound or complexed to a metal to be removed, the metal binding agents and chelators are can be separated (e.g., filtered, etc.) from the food material during processing. In some embodiments, the metal binding agents and chelators are organic certifiable.