Diabetes enhances the palatability of glycerol and glucose

Male rats were provided with flavored solutions (0.3 M glucose, 0.3 M glycerol or 0.6 M glycerol) or water before and after the induction of diabetes by streptozotocin. Normal animals given 0.3 M glucose showed a significant increase in fluid intake but normal animals offered the glycerol solutions did not show an increase in intake compared to animals given water. After the onset of diabetes, exposure to the same flavored solutions resulted in significant increases in fluid intake by animals offered both the glycerol and glucose solutions. The animals offered glucose consumed significantly more than did the animals offered the glycerol solutions. The animals offered 0.6 M glycerol consumed significantly more than did the animals offered 0.3 M glycerol on 8 out of the 10 days of exposure. Therefore, while diabetes does not appear to modify the palatability of glucose it seems to produce an enhanced palatability for glycerol not seen in normal rats.