To improve the heat retention by diapers and other absorbents, a heat retention indicator 1 of a water-absorbing resin which is defined in the present invention needs be 3.0° C./min or less and also that particular requirements need be met to satisfy this condition. If the requirements are met, a water-absorbing resin, absorbent, and absorbent article can be provided which has a heat retention indicator 1 of 0 to 3.0° C./min or less and which exhibits excellent heat retention and absorption.
