Metabolic Impacts of Food Oral Processing

The metabolic impact of oral processing is often overlooked in food design and when considering diet and lifestyle interventions to improve health and post-prandial metabolism. Food oral processing is the first step in the digestion and absorption of nutrients and informs a cascade of neuroendocrine and metabolic responses that occur post-ingestion. A food's physical, mechanical and lubricant properties inform how we adapt the duration and extent of oral processing during mastication, which, in turn, influences the incorporation of saliva and the surface area of the bolus. The properties of a food bolus at swallow can alter digestive kinetics and the rate and extent of post-prandial changes in the plasma concentrations of nutrients, in addition to the endocrine signals linked to feelings of satiety during the post-meal period. This chapter summarizes our current understanding of the metabolic impact of oral processing from acute feeding trials, long-term interventions and population-based studies. We focus on the impact of oral processing on post-prandial glucose and insulin responses, and energy intake and satiety, as they relate to body weight and metabolic health. We describe the impact of oral processing on gastric emptying and diet-induced thermogenesis. We provide an overview of the potential applications of these findings to food design and eating interventions that can be used to promote healthier diets and food intake behaviour. A better understanding of the metabolic impact of oral processing behaviour for specific consumer groups could assist in steering sensory perception, food choice and eating behaviour to promote healthier metabolic responses.