1. A method for informing a user of an intoxication state over time, comprising: at a sample receiving module coupled to a wrist-borne device, receiving a set of samples from a body region of the user within a time window; at a processing subsystem in communication with the wrist-borne device, generating a sample signal derived from an interaction between the set of samples and a fuel cell sensor in communication with the sample receiving module; at the processing subsystem, determining a predicted temporal profile of an alcohol content metric from the sample signal, the predicted temporal profile including a predicted value of the alcohol content metric at a time point outside of the time window; and transmitting a set of commands, from the processing subsystem to a user interface device coupled to at least one of the processing subsystem, the sample receiving module, and the wrist-borne device, that prompt the user interface device to provide an output derived from the predicted temporal profile to the user.