Provided is a method of constructing a database in which data representing a user's real state is accumulated. The method of constructing a database includes: a step (a) for acquiring, in real time, first information that changes in accordance with a user's state, using a vital data acquisition means attached to the user's body or installed in the vicinity of the user； a step (b) for acquiring one or more types of second information different from the first information； a step (c) for analyzing the correlation of the first information with the second information； and a step (d) for associating the user's state with the second information on the basis of the result of analysis of the correlation.
