Disclosed is an apparatus for measurement of a living body, comprising: a personal data input unit a basal metabolism input unit a standard value storage unit a comparison unit and a display unit. According to the invention the personal data input unit enters at least an age of a person to be measured, the basal metabolism input unit enters a basal metabolism of the person to be measured, and the standard value storage unit stores standard values of basal metabolism according to the ages. Furthermore, the comparison unit compares the basal metabolism entered by the input unit with the standard values of basal metabolism according to the ages stored in said storage unit, and calculates a basal metabolic age indicating what age the basal metabolism of the person to be measured corresponds to. Then, the display unit displays the information about the calculated basal metabolic age.