No abstract

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:

Objective: To examine whether high carbohydrate meals with different carbohydrate digestion rates have an effect on the short-term satiety in normal and obese preschool children. Subjects and setting: In total, 48 children of both gender, 24 normal and 24 obese, according to body mass index, aged between 3 and 6 y, were selected from children who were attending to a day-care center where they consumed three meals in the day. Interventions: Rapid (potato-based meal) and lente (spaghetti-based meal) carbohydrate digestion rate meal were given at lunch, matching energy intake, carbohydrate, protein and fat levels, and then the preschool children's energy intake at the subsequent mealtime was observed. In this last mealtime, the children received varied types of high-acceptability foods in higher quantities than the normal serving. Results: At lunch, a significant higher energy intake, lesser satiation, was observed in both groups, normal-weight and obese children, when they consumed the potato-based meal. In the subsequent mealtime, a significant effect of carbohydrate digestion rate was demonstrated, but only in obese preschool children, being higher in the meal with rapid digestion rate carbohydrates. Conclusions: Rapid carbohydrate digestion rate meal produced a significative lesser satiation in normal-weight and obese children. However, only in obese children a significant lesser satiety was observed after consumption of the rapid carbohydrate digestion rate meal, indicating a decreased capacity of energy regulation in obese children. The finding of the present work could provide dietary strategies required for decreasing prevalence in overweight and obesity in preschool children.

A study was performed to examine the rate of digestion of available carbohydrate in legumes and its mixtures with cereals, prepared as commonly eaten. The legumes and cereals studied were lentil (Lens sculenta), pea (Pisum sativum), bean (Phaseolus vulgaris, var tortola), rice (Oryza sativa) and spaghetti. Foods were purchased at the city market. Total starch content and the carbohydrate digestion rates were determined using the enzymatic method proposed by Englyst et al. Total starch levels ranged from 7.78 g/100 g in cooked flour bean to 20.6 g/100 g in a bean-spaghetti dish, and dietary fiber contents ranged from 2.4 g/100 g in a cooked 70:30 lentil-rice mixture to 5.26 g/100 g in a cooked whole bean. The rapid digestion rate carbohydrates showed values from 4.8 in the bean soup to 8.9 in the bean-spaghetti combination. The same results show, expressed as rapid available glucose (RAG), the amount of rapid carbohydrate/100 g food or meal as eaten, and as the starch digestion index (SDI), the percentage of rapid carbohydrate digestion rate in relation to the total amount of carbohydrate. The RAG values ranged between 5.0 for cooked beans and 10 for cooked beans and spaghetti, and the SDI ranged between 40 for cooked pea flour and 62 for cooked bean flour. Legumes prepared as soup showed a higher rapid digestion rate than legumes prepared as whole grain. The bean-spaghetti based-meal and the lentil-based meal showed glycemic index mean and standard deviation values of 76.8 +/- 43.4 and 49.3 +/- 29.5, RAG values of 7.0 and 6.0, and SDI values of 57 and 54, respectively. The knowledge of the importance of the carbohydrate digestion rates in human health in increasing, and probably will soon be used in the development of the food pyramid. The foods with a moderate fraction of rapid digestion rate, such as legumes, should be included in the base of the pyramid.