Increased chewing reduces energy intake, but not postprandial glucose and insulin, in healthy weight and overweight young adults

Abstract

Aim: This randomised cross-over design study aimed to investigate different chewing activities between healthy weight and overweight individuals and to determine the effect of chewing on energy intake and postprandial plasma glucose and insulin concentrations. Methods: Forty-one participants were classified into healthy weight and overweight groups according to body mass index (BMI). In Phase I, bite size (g/bite), bite rate (bites/minutes), chewing frequency (chews/minutes) and chews (chews/g food) were recorded after a sandwich breakfast. In Phase II, the mass of a sandwich consumed after 15 and 50 chews per bite (results of Phase I) was recorded. Postprandial plasma glucose and insulin were also examined at 0 (baseline), 30, 60, 90, 120 and 180 minutes. Results: The results showed that the number of chews per bite was higher in lean participants as compared to overweight participants. Energy intake was highest in overweight participants who chewed 15 times per bite. Additionally, participants consumed less energy after 50 chews regardless of their BMI status. The results also demonstrated that 50 chews per bite insignificantly increased plasma insulin concentrations at every time point in both lean and obese subjects. Insulin concentrations were not significantly changed at each time point regardless of the number of chews. Conclusions: Overweight participants chewed less and ingested more calories. Chewing 50 times per bite could reduce caloric intake regardless of weight status, suggesting that slow eating via increased chewing may help to reduce energy intake during meals. However, chewing did not affect postprandial plasma glucose and insulin levels in healthy young adults.