Impact of Individual Differences in Eating Rate on Oral Processing, Bolus Properties and Post-Meal Glucose Responses

• Published in: Physiology & behavior 2021-09, Vol.238, p.113495-113495, Article 113495
• Main Authors: Goh, Ai Ting, Chatonidi, Georgia, Choy, Michelle, Ponnalagu, Shalini, Stieger, Markus, Forde, Ciarán G.
• Format: Article
• Language: English
• Subjects: Eating behaviour; Eating rate; Food texture; Glycaemic Response
• ISSN: 0031-9384; 1873-507X
• DOI: 10.1016/j.physbeh.2021.113495

•Eating faster is associated with higher energy intake, and may also affect glycaemic and insulin responses.•We compared whether oral processing behaviours, bolus/saliva properties and post-prandial glucose responses differed between slow and fast eaters.•Eating rate, oral exposure time and bolus saliva uptake were the best predictors of post-prandial glycaemic response.•Differences in eating rate influenced temporal changes in post-prandial glucose, but not total post-prandial glucose release or bolus properties. Modifying food texture has been shown to influence oral processing behaviour. We explored the impact of food texture on oral processing, bolus formation and post-prandial glucose responses (PPG) among fast and slow eaters. Male participants (N=39) were split into fast or slow eaters based on natural differences in eating rate when consuming two carbohydrate-equivalent test-meals differing in texture (white rice and rice cake). PPG and satiety responses were compared for fast and slow eaters over 120-min for each test-meal. Each groups test-meal PPG was compared for bolus and saliva properties at the point of swallow. White rice displayed lower instrumental hardness, chewiness and Young's modulus and was perceived less chewy, springy and sticky than rice cake. Slow eaters (n=24, white rice: 13.3 g/min; rice cake: 15.1 g/min) required an average 42% more chews per bite (p < 0.001), had 60% longer oral exposure time (OET), and consumed both test-meals (p < 0.001) at half the eating rate of fast eaters (n=15). Slow eaters had higher PPG following the rice cake meal at 15 (p = 0.046) and 45 min (p = 0.034) than fast eaters. A longer OET was a positive predictor of early PPG at 30-min after the white rice meal (β = 0.178, p = 0.041) and saliva uptake was a significant predictor (β = 0.458, p = 0.045) of PPG for slow eaters when consuming rice cake. Increasing food hardness and stiffness (Young's modulus) had a greater impact on eating rate for slow eaters than fast eaters. Eating rate, oral exposure time and bolus saliva uptake were the predictors of an individual's post-prandial glycaemic response amongst slow eaters. Increasing the number of chews per bite with a longer oral exposure time increased saliva uptake in the bolus at the moment of swallowing and enhanced temporal changes in PPG, leading to greater glycaemic peaks in rice cake meal. Differences in eating rate between slow and fast eaters when consuming rice cake meal influenced temporal cha