Two potato meals containing 50 g of carbohydrate were fed to 9 subjects with varied insulin sensitivity, at mean temperatures of 83.6 degrees C for hot potato and 26.0 degrees C for cooled potato. Cooled potato resulted in a significantly lower mean postprandial blood glucose level, area under the glucose curve, glycemic index, and serum triglyceride concentration, compared with hot potato (p < 0.05).

Comment: This study demonstrates that the temperature at which a starchy food is consumed influences its glycemic index and its effect on postprandial triglyceride levels. It is possible that cooling a cooked food changes the chemical structure of the starch, thereby slowing the rate at which it is digested. Diabetics who have difficulty controlling their glucose levels with the usual dietary approaches might benefit from chilling their starchy foods before eating them.

Najjar N, et al. Glycemic and insulinemic responses to hot vs cooled potato in males with varied insulin sensitivity. Nutr Res 2004;24:993-1004.