Effect of low glycaemic index meals on insulin secretion in diabetic and apparently healthy subjects

Abstract

One of the potential effects of low glycaemic index (low-GI) diets is to reduce insulin secretion in patients with type 2 diabetes. The effects of low GI meals (Acha, Rice and Eba) on serum insulin were elicited in diabetic type 2 subjects. Ten diabetic and 6 healthy individuals participated in the
study. Fasting blood samples were taken and after consumption of the reference (glucose) and test meals (Acha, Rice and Eba) every 30 minutes until two and half hours post - consumption. Serum blood glucose level was determined using glucose oxidase method while insulin level was
determined using Enzyme-Linked Immunosorbent Assay (ELISA). Insulin responses to the various meals in the diabetic subjects were initially lower (p<0.05) compared to those in the control and also the insulinogenic indices were significantly lower in the diabetics than the control (p<0.05). In the type 2 diabetic patients however, despite higher increments of serum glucose, only modest changes of plasma insulin occurred initially but later the insulin responses continued to increase up to two and half hour but the hyperglycaemia continued leading to a much lower ratio. This is to show that there is a state of impaired pancreatic beta-cell function since insulinogenic index is a measure of â -cell secretary function and also the insulin produced is not effective. Therefore, diabetic individuals consuming low glycaemic meals may not be producing effective insulin to clear the hyperglycaemia being produced by these meals.

Keywords: type 2 diabetics, low glycaemic index, insulin, insulinogenic indices