Palatability of sucrose before and after glucose ingestion in dieters and nondieters.

The present study examined the pleasantness of sucrose solutions as rated by dieters and nondieters, before and after the ingestion of a glucose solution. Subjects were 36 University of Toronto female undergraduates between 18 and 21 years old. After a 12 hour overnight fast, each subject tasted and rated five concentrations of sucrose solutions (2.5, 5.0, 10.0, 20.0, and 40.0%) for pleasantness and sweetness, at three minute intervals, over five separate trials. Two trials were run before the ingestion of a 200 ml 25% glucose solution and three trials after. The dieters rated the 20% and 40% sucrose solutions tasted prior to glucose ingestion as significantly less pleasant than did the nondieters; this difference was evident after glucose ingestion as well. A decrease in the palatability of the sucrose solutions induced by the glucose load (negative alliesthesia) was evident in both groups of subjects. Results were interpreted as requiring reconsideration of the assumption that dieters are below their set-points for body weight. Consideration of the role of cognitive factors in the perceived palatability of sweets may also be required.