We aimed to examine the effects of variable timing of carbohydrate intake on postprandial glucose and insulin excursion in a diet with the same levels of energy and balance of three major nutrients. The study subjects included 8 healthy individuals, mean age 20.0±1.2 y (4 males and 4 females; mean age, 19.1±0.7 and 20.8±0.9 y, respectively), without a family history of diabetes. They consumed a test meal consisting of three separate plates of rice, vegetables, and meat after an overnight fast. The subjects consumed the three plates in different orders on three different days; the subsequent changes in glucose and insulin levels were measured over a 120-min period. The participants who consumed rice at the end showed a significantly lower increase in glucose and insulin levels after 30 min of consumption than that shown by participants who consumed rice first. The areas under the curves for both glucose and insulin responses over 120 min were the least when rice was consumed last, whereas they were the greatest when rice was consumed first. These findings suggested that consuming carbohydrates at the end of a meal is associated with lower postprandial excursions of glucose and insulin. In conclusion, consuming carbohydrates last following vegetables and meat protects against postprandial excursions of glucose and insulin levels.
Keywords: carbohydrate; eating order; glucose excursion; insulin.