Mastication Patterns in Humans: Gender Differences

Abstract

Nineteen young healthy subjects were offered a morsel of hard (walnut) and soft (cake) food, while surface EMG was recorded bilaterally from the masseter muscles. The duration of the entire sequence of chewing, chewing rate, number of chewing cycles, time/cycle ratio, and mean and maximum EMG amplitudes of the above muscles were compared in women and men (n = 12 and 7, respectively). The duration of the whole chewing sequence for the soft food and duration of a single chewing cycle for both food types were significantly longer in women (P = 0.000). The masticatory frequencies for both food types were significantly greater in men (soft food: 0.98 ± 0.18 and 1.79 ± 0.18 sec–1, hard food: 1.25 ± 0.29 and 2.03 ± 0.32 sec–1 in women and men, respectively; P = 0.000). The numbers of chewing cycles for both food types were statistically similar (P = 0.38 and P = 0.67). The mean and maximum EMG amplitude were found to be nearly similar in women and men, except that the mean amplitude of the right EMG at soft food chewing was significantly higher in men (P = 0.02). Thus, chewing in women occurs, in general, more slowly, while masseter muscle activities are rather similar. The food consistency exerts a mild overall influence on the gender differences of chewing.