Body weight management device for managing a measurement subject's body weight using a target

A body weight management device comprising:

• a change obtainment unit configured to obtain an intra-day body weight change value on a daily basis based body weight measurement values of a measurement subject measured on a daily basis;
• an achievement rate obtainment unit configured to compare the intra-day body weight change value obtained by the change obtainment unit with an intra-day target weight loss value and obtaining, based on a result of the comparison, a target achievement rate indicating a percentage of days, in a total number of days in a predetermined period, in which the intra-day body weight change value has reached the intra-day target weight loss value;
• and
• a target obtainment unit configured to obtain, based on the magnitude of a difference between the target achievement rate obtained by the achievement rate obtainment unit and a threshold, a new intra-day target weight loss value to serve as a target for future body weight measurement.