Provided are an information processing device, a digestion rate estimation method, an information processing system and a digestion rate estimation program that are capable of providing a service on the basis of the digestion rate of food which a user has eaten to the user in real time. This information processing device estimates the digestion rate of food which a user has eaten and comprises: a first receiving unit for receiving a plurality of pieces of heart rate information measured at predetermined time intervals from a heart rate measurement device carried by the user a second receiving unit for receiving information of a meal start time and a meal finish time of the user a line calculation unit for calculating, on the basis of a trend shown by the plurality of pieces of the heart rate information in which the heart rate increases with time after the meal and then decreases, a primary approximation line that approximates the trend a correction unit for correcting the primary approximation line on basis of a trend shown by the plurality of pieces of the heart rate information in which the heart rate increases with time during the meal and then decreases a time specification unit for specifying a digestion finish time indicating the time when digestion of the food is completed on the basis of the corrected primary approximation line and the heart rate at the meal start time and a digestion rate estimation unit for estimating the digestion rate at the present time on the basis of the meal finish time and the specified digestion finish time.La présente invention concerne un dispositif de traitement dinformations, un procédé destimation de taux de digestion, un système de traitement dinformations et un programme destimation de taux de digestion qui sont capables de fournir un service à lutilisateur sur la base du taux de digestion daliments quun utilisateur a consommé en temps réel. Ce dispositif de traitement dinformations estime le taux de digestion daliments quu
