An information processing system 100 includes an information acquiring unit 110 that performs acquisition processing for information, a processing unit 120 that performs processing on the basis of the acquired information, and an output processing unit 130 that performs output processing for information created by the processing unit 120. The information acquiring unit 110 performs the acquisition processing for at least two kinds of information among staying time information, body information, and target information concerning a weight loss. The processing unit 120 creates advice information concerning the weight loss on the basis of a relational expression representing a relation between fluctuation in body weight or a body fat amount and the staying time information and the at least two kinds of information. The output processing unit 130 performs the output processing for the advice information.
