Effect of chewing speed on energy expenditure in healthy subjects

Abstract

Objective. The aim of the study was to investigate the effect of rate of chewing on energy expenditure in human subjects. Materials and methods. Fourteen healthy subjects (aged 18–24 years) within the normal range of BMI participated in a cross-over experiment consisting of two 6-min sessions of gum chewing, slow (∼60 cycles/min) and fast (∼120 cycles/min) chewing. The resting energy expenditure (REE) and during gum chewing was measured using a ventilated hood connected to a gas analyzer system. The normality of data was explored using the Shapiro-Wilk test. The energy expenditure rate during chewing and the energy expenditure per chewing cycle were compared between the two chewing speeds using Wilcoxon signed ranks tests. Results. The energy expenditure per chewing cycle during slow chewing (median 1.4, range 5.2 cal; mean 2.1±1.6 cal) was significantly higher than that during fast chewing (median 0.9, range 2.2 cal; mean 1.0±0.7 cal) (p < 0.005). However, the energy expenditure rate was not significantly different between the two chewing speeds (p > 0.05). Conclusions. The results of this study suggest that chewing at a slower speed could increase the energy expenditure per cycle and might affect the total daily energy expenditure.