The purpose of the present disclosure is to provide a computer, an information processing method, and a network system by which information relating to a trend of a mental or physical state of a subject can be acquired more easily than before. Provided is a computer including: a memory configured to store first data obtained from a strand of hair acquired from a subject and second data obtained from a specimen acquired from the subject, the specimen being different in acquisition time from the strand of hair; and a processor configured to generate a trend of a mental or physical state of the subject based on the first data and the second data.