Investigating Inter-individual Variability in Glycemic and Insulin Responses

Overview

This study aims to test the following hypothesis in healthy lean young men: * There are differences in glycemic response (GR) and insulin response (IR) between Chinese, Malay and Asian-Indian * There are differences in GI values to the same food between ethnic groups * There are ethnic differences postprandial GR and IR for high vs low GI foods * Mastication, salivary amylase activity, gastric emptying rate and gut microbiota composition influences inter-individual glycemic and insulinemic variability * Ethnic differences in mastication, salivary amylase activity, gastric emptying rate and gut microbiota composition determines the inter-ethnic glycemic and insulinemic variability

There is extensive evidence that numerous biological digestive factors varies between individuals and influence postprandial glycemic response (GR) and insulin response (IR), which are well established risk factors that precipitate the development of Type 2 diabetes mellitus (T2DM). However, no study to date has measured and compared physiological parameters such as mastication, salivary amylase activity, gastric emptying rates and gut microbiota in a multi-ethnic Asian population, with varying prevalence of obesity and T2DM. The aim of this study is to investigate ethnic differences in GR and IR as well as the GI values of foods. Additionally, we aim to examine how physiological digestive factors contribute to inter-ethnic and inter-individual variability in GR and IR. The study outcomes can potentially explain, in part, the varying susceptibility to obesity, T2DM and DM control between Chinese, Malays and Asian-Indians in Singapore, as reflected by the differences in prevalence of obesity, T2DM and DM control among the three local ethnic groups.