An information processing apparatus comprising: a memory (1600, 1700, 1800); and a processor coupled to the memory and configured to: acquire from the memory (1600, 1700, 1800) time series data representing heart rate as a function of time for each of a plurality of days and for the same person, apply statistical processing to the time series data to obtain a waveform of average heart rate data representing statistical heart rate for the same period of time of the plurality of days, extract, from the waveform representing statistical heart rate, a peak time zone in which a width of the average heart rate data on the waveform representing statistical heart rate increases to be equal to or greater than a first threshold value and a rising period of the heart rate is equal to or larger than a second threshold value, detect, in a waveform of time series data of a given day, a second time zone that includes the peak time zone and has a shape similar to the waveform of the peak time zone, detect, in the waveform of time series data of the given day, a peak in which a width of the time series data representing heart rate on the waveform of time series data of the given day increases to be equal to or greater than a predetermined threshold, the peak occurring at the start time of the second time zone or within a predetermined period before the start of the second time zone, the peak representing an estimated meal time, and output the estimated meal time. a memory (1600, 1700, 1800); and a processor coupled to the memory and configured to: acquire from the memory (1600, 1700, 1800) time series data representing heart rate as a function of time for each of a plurality of days and for the same person, apply statistical processing to the time series data to obtain a waveform of average heart rate data representing statistical heart rate for the same period of time of the plurality of days, extract, from the waveform representing statistical heart rate, a peak time zone in which a width of the average heart rate data on the waveform representing statistical heart rate increases to be equal to or greater than a first threshold value and a rising period of the heart rate is equal to or larger than a second threshold value, detect, in a waveform of time series data of a given day, a second time zone that includes the peak time zone and has a shape similar to the waveform of the peak time zone, detect, in the waveform of time series data of the given day, a peak in which a width of the time series data representing heart rate on the waveform of time series data of the given day increases to be equal to or greater than a predetermined threshold, the peak occurring at the start time of the second time zone or within a predetermined period before the start of the second time zone, the peak representing an estimated meal time, and output the estimated meal time. acquire from the memory (1600, 1700, 1800) time series data representing heart rate as a function of time for each of a plurality of days and for the same person, apply statistical processing to the time series data to obtain a waveform of average heart rate data representing statistical heart rate for the same period of time of the plurality of days, extract, from the waveform representing statistical heart rate, a peak time zone in which a width of the average heart rate data on the waveform representing statistical heart rate increases to be equal to or greater than a first threshold value and a rising period of the heart rate is equal to or larger than a second threshold value, detect, in a waveform of time series data of a given day, a second time zone that includes the peak time zone and has a shape similar to the waveform of the peak time zone, detect, in the waveform of time series data of the given day, a peak in which a width of the time series data representing heart rate on the waveform of time series data of the given day increases to be equal to or greater than a predetermined threshold, the peak occurring at the start time of the second time zone or within a predetermined period before the start of the second time zone, the peak representing an estimated meal time, and output the estimated meal time.