Glycaemic Response in Relation to Gastric Emptying and Satiety in Health and Disease

University dissertation from Department of Clinical Sciences, Lund University

Abstract: Dietary fibre and whole grains are recommended to prevent the development of type 2 diabetes. Low glycaemic index foods that are rich in fibre are recommended to control blood glucose levels. Gastric emptying, together with other factors, regulate the postprandial blood glucose response. A delay in the gastric emptying rate (GER) leads to a lower postprandial blood glucose concentration. However, 30-50% of diabetes patients have delayed gastric emptying.The aims of these studies were to evaluate the effect of different food factors on the GER, the postprandial blood glucose response, and satiety in healthy subjects and those with diabetes mellitus. The results show that inclusion of 6 g cinnamon in the diet lowers the postprandial blood glucose response, a change that is at least partially explained by delayed GER. Neither bran flakes nor wholemeal oat flakes has any effect on the total postprandial blood glucose response, GER or satiety compared with cornflakes. Muesli with 4 g oat β-glucan does not affect the GER or satiety, but lowers the postprandial blood glucose response, indicating that the GER is not involved in the blood glucose lowering mechanism. Whole-kernel wheat bread served with vinegar leads to higher satiety than wholemeal wheat bread with vinegar, or white wheat bread with or without vinegar in healthy subjects. This may be explained by increased antral distension caused by intact cereal kernels, but not by changes in GER or postprandial blood glucose responses. Vinegar affects insulin-dependent diabetes mellitus patients with diabetic gastroparesis by reducing the GER even further.