Investigating Inter-individual Variability in Glycemic and Insulin Responses

Not Applicable

Completed

• Conditions: Hyperglycemia; Insulin Sensitivity
• Interventions: Other: Jasmine rice; Other: Parboiled basmati rice

• Registration Number: NCT01804738
• Lead Sponsor: Institute for Human Development and Potential (IHDP), Singapore

Brief Summary

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

Detailed Description

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.

Study Timeline

• Study Start: 2013-03
• Study First Submitted: 2013-03-04
• Study First Submitted QC: 2013-03-04
• Study First Posted: 2013-03-05
• Primary Completion: 2014-06
• Study Completion: 2014-06
• Status Verified: 2019-03
• Last Update Submitted: 2019-03-12
• Last Update Posted: 2019-03-14

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 75

Inclusion Criteria

• Be willing and able to comply with study procedures and given written informed consent
• Chinese/Malay/Indian males, aged 21-40 years old
• Body mass index (BMI) between 18.5 - 24.9 kg/m2
• Fasting blood glucose between 4 - 6 mmol/L
• Sedentary adults, with <1 episode of exercise per week
• Not have a history of food allergies or food intolerances
• Be a non-smoker
• Drinks less than 3 units of alcohol per day
• Not taking antibiotics for the past 3 weeks

Exclusion Criteria

• Subjects with known chronic diseases, including diabetes, untreated hypertension, renal impairment, gastrointestinal problems, and other significant medical conditions
• BMI <18.5 kg/m2 or >25 kg/m2
• Fasting blood glucose ≥7.0mmol/l
• Alcohol consumption >3 drinks / day
• Use of medications known to affect glucose metabolism
• Recent changes in weight of >5% over the past 3 months
• Significant changes in diet over the past 3 months
• History of eating disorders or irregular eating habits
• Taking antibiotics medications over the past 3 weeks

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Jasmine rice	Jasmine rice	50g available carbohydrate portion
Parboiled basmati rice	Parboiled basmati rice	50g available carbohydrate portion

Primary Outcome Measures

Name	Time	Method
Postprandial glycemic and insulin responses	Every 15 mins in the first hour and every 30 mins for the next 2 hours after food consumption	Capillary bloods will be obtained using finger-pricks

Secondary Outcome Measures

Name	Time	Method
Physiological digestive functions	Up to 5 hours	They include: measurement of mastication rate, salivary amylase activity, gastric emptying rate and gut microbiota composition

Trial Locations

Locations (1)

Clinical Nutrition Research Centre; 🇸🇬 Singapore, Singapore