Taste impairment for glucose in diabetic PTC tasters and non-tasters.

Effect of high blood glucose levels in diabetes mellitus was studied on gustatory responses to glucose in PTC tasters and non-tasters, before and after the ingestion of a glucose solution. After a 12-h overnight fast, prescreening for phenylthiocarbamide (PTC) sensitivity was done in each subject, and then each subject tasted, and rated, 7 concentrations of glucose solutions for intensity and hedonic responses. Blood glucose levels were also determined under fasting and then after a 100-g glucose load. A decrease in palatability of the glucose solutions induced by the glucose load (negative alliaesthesia) was evident in both groups of subjects. Tasters showed higher hedonic ratings (Mean 4-25), as compared to non-tasters (Mean 3-70) and this difference was more evident after the glucose load in non-tasters.