The influence of mandibular movement timing on food breakdown remains unclear. The authors, therefore, sought to relate chewing rate with masticatory performance. Chewing rate, defined as the number of masticatory cycles habitually achieved per minute, was measured in 55 healthy dentulous subjects (age, 22.2 +/- 5.0 years). Subjects were grouped according to obtained values (cycles/minute): slower: < 70; middle: 70-90; and faster: > 90. Masticatory performance was determined through the sieve method, and the estimated comminuted median particle size (X50). Data was analyzed using the one-way ANOVA and chi-square tests (alpha = .05). Subjects with slower chewing rates showed higher (p < .05) masticatory performance (X50 = 3.05 +/- 0.77 mm). X50 was associated with chewing rate when subjects were categorized as better or poorer performers (chi-square = 11.25, p < .005). Thus, chewing rate was related to masticatory performance, with smaller food particles being achieved with a slower chewing rate.