Blodsocker- och insulinrespons efter intag av rågextrakt

Sammanfattning:

A high blood glucose concentration is one of many factors that can contribute to the development of type 2 diabetes, which is a world-spreading disease. Many studies have been done on products that can lower the glycaemic response and one of these products is the grain rye. Whole grain rye and endosperm from rye have shown positive results on the blood glucose and insulin responses after carbohydrate intake in former studies. In this randomised crossover meal study, a special rye extract, rich in soluble fibres, was used to investigate if it gave the same blood glucose and insulin results as in previous studies.

The rye product that was used is this study was obtained by a confidential extraction process. The rye extract was found to contain 20.4 g dietary fibres per 100 g dry weight and the rye drink that was served to the test subjects contained 4 g dietary fibre. The rye product and the reference product were both mixed with Fun Light soda for better taste. After the rye or reference drinks had been taken, white bread and water was consumed.

In this randomised crossover intervention study, 16 healthy subjects participated and they were all recruited from Lund University. The subjects were men and women in the age of 20-33 with normal fasting blood glucose concentrations and a BMI range of 19-26. The subjects were randomly assigned to drink the rye drink or the reference drink on the first intervention day and the other drink the second time.

On the intervention days the blood glucose and insulin concentrations were immediately determined by capillary measurement at fasting conditions (time -15) before the subjects began to drink their test- or reference drink during 15 minutes. After the drinks had been taken, the blood sugar concentration was measured (time 0) before the white bread and water were ingested. The blood sugar and insulin concentrations were then measured at 15, 30, 45, 60, 90, 120 and 180 minutes from when the test subjects started to eat the white bread.

The rye product displayed a lower incremental glucose response (p= 0.008) and a lower iPeak value (maximum value) than the reference product (p=0.002). Both GP and GPI were higher for the rye meal (p= 0.009 and p= 0.018). The insulin values did not differ significantly from each other in comparison with the reference meal.

The rye product showed similar reduced blood glucose responses compared to its reference product as previous studies have shown. In contrast, the rye product did not show the same positive result on the insulin values. The rye products relatively lower blood glucose response may largely be due to the rye products content of arabinoxylan, which explains the rye drinks viscosity. The viscosity has in previous studies resulted in a slower gastric emptying rate and a slower absorption of glucose in the small intestine like it also looks to have done in this study.