Background and aim: Cereal products with low postprandial glycemic response are encouraged in the management of hyperglycemia. In this study, we determined the postprandial glycemic response of two different oat bran products in patients with type 2 diabetes. In addition, we investigated the effects of oat bran flour on postprandial glucose response following an oral glucose load.
Methods and results: A randomized, controlled, repeated measures design with two test series was used. Twelve type 2 diabetic patients participated in five 2-h meal glucose tolerance tests on separate occasions. Volunteers were given in random order oat bran flour, oat bran crisp and glucose load providing 12.5 g glycemic carbohydrate (series 1), 25 g glucose load alone and 25 g glucose load with 30 g oat bran flour (series 2). Finger-prick capillary blood analysis was carried out fasting and then 15, 30, 45, 60, 90 and 120 min after the start of the meal. The oat bran flour had a lower 0-120 min area under the glucose response curve (AUC) (47+/-45 mmol min/L) than the glucose load (118+/-40 mmol min/L) (p<0.002), but there was no difference between the oat bran crisp (93+/-41 mmol min/L) and the glucose load in this respect. The oat bran flour decreased the glucose excursion from baseline by 1.6 mmol/l (2.4, 0.8) (mean (95% CI)) and 1.5 mmol/l (2.0, 1.1) at 30 and 45 min after the glucose load, respectively.
Conclusions: Oat bran flour high in beta-glucan had a low glycemic response and acted as an active ingredient decreasing postprandial glycemic response of an oral glucose load in subjects with type 2 diabetes.