A superabsorbent obtainable by a process for producing superabsorbents by polymerizing a monomer solution comprising a) at least one ethylenically unsaturated monomer which bears acid groups and is optionally present at least partly in salt form, b) at least one crosslinker, c) at least one initiator, d) optionally one or more ethylenically unsaturated monomers copolymerizable with the monomers mentioned under a), e) optionally one or more water-soluble polymers, the process further comprising drying of the resulting polymer and optionally grinding of the dried polymer and sieving of the ground polymer and optionally surface postcrosslinking of the dried and optionally ground and sieved polymer, wherein at least one sulfonic acid derivative is added to the monomer mixture and/or to the polymer prior to the drying, and at least one phosphonic acid derivative is added to the polymer after the drying or optionally after the surface postcrosslinking, exhibits improved stability to discoloration in the course of storage at elevated temperatures or under elevated air humidity.