Influence of Experimentally Induced Taste Disorder on Ingestive Behavior: A Pilot Study

Abstract

This study was aimed to gain insights on how impaired taste sensation alters ingestive behavior. Gymnema sylvestre extract was applied to the tongue surface to create an experimentally induced taste disorder (EITD). The ingestive behavior and the rheological properties of the food bolus just before the first swallowing were compared between with and without EITD in six healthy volunteers who ingested a chocolate chip cookie. Although EITD made the bolus significantly less hard, less adhesive and more cohesive (Wilcoxon's rank-sum test; P < 0.001), and make the jaw gape of the chewing cycles just before the first swallowing smaller (P < 0.05) in all participants, its effect on the number of chewing cycles until swallowing was heterogeneous. The results suggest that EITD may alter ingestive behavior not through a reduction of the perceived tastes but through a reduction in the palatability and/or the intensity of the unpalatability of a food. Practical Applications The results of the current study suggested that a reduction in the palatability and/or the intensity of the unpalatability of a food, i.e., the uncomfortable emotions elicited by the alteration of perceived taste of a food, may have significant effects on the ingestive behaviors of persons with experimentally induced taste disorder. The results further suggested the importance of enhancing palatability and reducing unpalatability of the food by activating the residual gustatory and/or olfactory functions to improve the affected ingestive behavior of the patients who suffer from taste disorders.