A comparison between an in vitro method to determine carbohydrate digestion rate and the glycemic response in young men

Objective: This study examines the relationship between the results of in vitro determinations of carbohydrate digestion rates and the glycemic index. Subjects: Ten healthy non smoking men, aged between 21 and 24-y-old, were selected to participate in the study. Methods: Six different meals with similar lelvels of carbohydrates were assayed at breakfast in ten subjects and blood samples were obtained at 0, 15, 30, 60 and 120 min to determine glucose levels. The Englyst's enzymatic method was used in the in vitro study. The six meals were based in cereals (rice or spaghetti); legumes (lentil soup and beans with spaghetti); and potato (potato stew with meat and vegetables). Results: The meals showed different glycemic indices: rice and spaghetti based meals had lower values (mean value 31.4 and 42, respectiively); the intermediate values corresponded to lentil soup and the bean dish (49.3, and 76.8 respectively) and the higher glycemic index was shown by the potato based meal (82). Conclusions: A significant correlation was observed when the ratio of rapid carbohydrate digestion rate and the lente carbohydrate digestion rate was correlated with the glycemic index of the meals, but not when only the rapid carbohydrate digestion rate was considered. These results demonstrate a useful, simple and inexpensive method to estimate the biological response of high carbohydrate meals. Sponsorship: University of Chile, Faculty of Medicine, Department of Nutrition and Grant No 1980893 from FONDECYT.