Lowered blood glucose and insulin responses after a mixed breakfast, with PrimalivTM a yoghurt with a OatWell® beta-glucan enriched müsli

Abstract

There is convincing documentation, demonstrating positive metabolic effects of a diet containing low GI products in diabetics and hyperlipidemic subjects. Epidemiological data also suggest that a low GI diet may prevent against diabetes type 2, cardiovascular disease, protect against the metabolic syndrome and reduce the prevalence of insulin resistance. Many staple foods, however, cause high blood sugar and insulin responses after meals. In this study the effect of PrimalivTM, a yoghurt containing 4 g of OatWell® betaglucan, on the subsequent blood sugar and insulin responses in a mixed breakfast meal, was determined in healthy subjects. Thirteen healthy voluntary subjects participated in the study. The test meal and reference meal was served as breakfast in random sequence. Test meal: PrimalivTM (200 g low fat vanilla yoghurt, 27 g müsli), 39.6 g white bread, butter and cheese. Reference meal: 200 g low fat vanilla yoghurt, 66.9 g white bread butter and cheese. The meals were standardised to 50 g digestible carbohydrates. The müsli was based on OatWell® an oat bran rich in beta-glucan and contained 4 g OatWell® beta-glucans per portion. Energy composition of the meals was about 60 E % carbohydrates and 20 E % of both protein and fat, respectively. Before meal, a capillary blood test was taken from each subject to determine fasting value for blood sugar and insulin. After meals blood samples were taken at 15, 30, 45, 70, 95 and 120 minutes. Determination of blood glucose was carried out using glucose oxidase peroxidase reagent. Insulin in serum was analysed using ELISA method. The test meal significantly lowered the glucose 36% and insulin 44% response, compared to the reference meal. The meal with müsli gave significantly lower glucose and insulin responses in the early post-prandial part (0-70 minutes) and a higher glucose level in the later response (95 minutes), which indicates delayed carbohydrate uptake. This quantity is in parity with that used in a study by Tappy et al (1996) in which significant and physiologically meaningful effects were found with 4.0 g OatWell® beta-glucan in a breakfast meal. The conclusion drawn is that the inclusion of a müsli containing 4 g OatWell® beta-glucan from oat moderates the post-prandial blood glucose and insulin response after a mixed breakfast in healthy subjects. The moderation is significant and is considered to be physiologically important, especially for individuals with glucose intolerance. Tappy, L. et al. 1996. Diabetes Care 19:831-834.