Glycaemic Index (GI) Evaluation of Carbohydrate-based Food with Functional Ingredients Derived from Food Sources

In Singapore, the Ministry of Health has declared a "War on Diabetes" and major efforts will be made to develop and deploy programs to prevent diabetes. One of the cornerstones of diabetes management involves dietary modifications to reduce postprandial hyperglycaemia. However, implementation of a low GI diet is highly complex requiring the individual to choose foods from a long list which are primarily based on western consumption patterns. Many foods in the Asian diet, which largely consist of carbohydrates such as white rice, noodles and other flour based products, are not represented. An alternative solution will require innovative ways to alter commonly available food products that will not only help reduce postprandial glycaemia but also preserve the sensory characteristics of the foods to create a new generation of food products both functional and palatable. One such approach is the incorporation of plant compounds that lower the glucose absorption from foods. The aim of the project is to measure the GI of carbohydrate-based food with edible plant derived molecules. Natural, plant-derived anthocyanin will be incorporated into bread to produce low GI bread. Anthocyanins are well known for its anti-oxidant activity and recent studies reported that anthocyanins also had an inhibitory activity against digestive enzymes that break down carbohydrates. It can potentially inhibit amylase, and suppress the increase in postprandial glucose level from starch. Bread is a carbohydrate-rich product, which contains a high amount of rapidly digestible starch, and therefore many of them have a high GI. This study aims to determine the glycaemic effects of anthocyanin fortified bread. The effort is designed to enable and inform population interventions that will have an impact on the health of the population in a sustainable manner by introducing innovative foods into the food supply that are 'health promoting' based on rigorous human experiments and are acceptable to the public and other major stakeholders.

Study Overview

• Status: Completed
• Conditions: Postprandial Hyperglycemia
• Intervention / Treatment: Dietary supplement: Anthocyanin

• Study Type: Interventional
• Enrollment (Actual): 24
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Singapore
  • Singapore, Singapore, 117599
    • Investigational Medicine Unit

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Ability to give informed consent
• Age between 21-65 years old
• Overtly healthy males or females, as determined by medical history, physical examination and laboratory results within normal reference range for the population or investigator site, or results with acceptable deviations that are judged to be not clinically significant by the investigator
• Males and females with stable medical problems that, in the investigator's opinion, will not significantly alter the performance of the biomarker panel, will not place the subject at increased risk by participating in the study, and will not interfere with interpretation of the data.
• Not on any regular medications (western / traditional medicine). Nutritional supplements with established chemical composition that can be ascertained and clearly recorded is acceptable.

However, subjects using traditional medicine (with compositions that cannot be ascertained) will be excluded in this study.

• Have venous access sufficient to allow for blood sampling as per the protocol
• Reliable and willing to make themselves available for the duration of the study and are willing to follow study procedures (participants are required to fast overnight for 10-12h before each visit).

Exclusion Criteria:

• History or presence of current cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrine, hematological, malignancy or neurological disorders capable of significantly altering the performance of the biomarker panel; or of interfering with the interpretation of data
• Known or ongoing psychiatric disorders within 3 years
• Regularly use known drugs of abuse within 3 years
• Women who are pregnant or lactating
• Have donated blood of more than 500 mL within 4 weeks of study enrolment

• Have an average weekly alcohol intake that exceeds 21 units per week (males) and 14 units per week (females):

  • 1 unit = 12 oz or 360 mL of beer;
  • 5 oz or 150 mL of wine;
  • 1.5 oz or 45 mL of distilled spirits
• Uncontrolled hypertension (blood pressure [BP] >160/100mmHg
• Active infection requiring systemic antiviral or antimicrobial therapy that will not be completed prior to Study Day 1
• Treatment with any investigational drug, or biological agent within one (1) month of screening or plans to enter into an investigational drug/ biological agent study during the duration of this study
• Known allergy to insulin
• History of bleeding diathesis or coagulopathy
• Any of the following laboratory values at screening:

Fasting glucose >=126mg/dL(>=7mmol/L) or 2 hour post-prandial glucose >=200mg/dL (>=11.1mmol/L)

• Clinically significant (as determined by investigator) abnormalities on laboratory examination that will increase risk to the patient or interfere with data integrity
• Have any other conditions, which, in the opinion of the Investigator would make the subject unsuitable for inclusion, or could interfere with the subject participating in or completing the study
• Significant change in weight (+/- 5%) during the past month

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: White bread
Experimental: Anthocyanin-fortified bread (2% w/w)	Dietary supplement: Anthocyanin; 25% w/w anthocyanin extract obtained from black rice
Experimental: Anthocyanin-fortified bread (4% w/w)	Dietary supplement: Anthocyanin; 25% w/w anthocyanin extract obtained from black rice

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Glycemic index	Change in incremental area-under-curve (min*mmol/L)	2 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Anthocyanin and metabolite bioavailability	Change in anthocyanin and anthocyanin metabolite concentrations (mg/L)	0 minutes, 60 minutes, 120 minutes
Oxidative stress	Change in total F2-isoprostane concentration (mg/L)	0 minutes, 60 minutes, 120 minutes

Collaborators and Investigators

• Sponsor: National University of Singapore
• Collaborators: National University Health System, Singapore
• Investigators: Principal Investigator: Mei Hui Liu, PhD, National University of Singapore

Publications and helpful links

General Publications

• Sui X, Zhang Y, Zhou W. Bread fortified with anthocyanin-rich extract from black rice as nutraceutical sources: Its quality attributes and in vitro digestibility. Food Chem. 2016 Apr 1;196:910-6. doi: 10.1016/j.foodchem.2015.09.113. Epub 2015 Oct 9.
• van Dam RM, Naidoo N, Landberg R. Dietary flavonoids and the development of type 2 diabetes and cardiovascular diseases: review of recent findings. Curr Opin Lipidol. 2013 Feb;24(1):25-33. doi: 10.1097/MOL.0b013e32835bcdff.
• Zhang PW, Chen FX, Li D, Ling WH, Guo HH. A CONSORT-compliant, randomized, double-blind, placebo-controlled pilot trial of purified anthocyanin in patients with nonalcoholic fatty liver disease. Medicine (Baltimore). 2015 May;94(20):e758. doi: 10.1097/MD.0000000000000758.

Study record dates

Study Major Dates

• Study Start (Actual): October 27, 2017
• Primary Completion (Actual): December 30, 2018
• Study Completion (Actual): December 30, 2018

Study Registration Dates

• First Submitted: June 14, 2019
• First Submitted That Met QC Criteria: June 14, 2019
• First Posted (Actual): June 18, 2019

Study Record Updates

• Last Update Posted (Actual): November 15, 2024
• Last Update Submitted That Met QC Criteria: November 13, 2024
• Last Verified: July 1, 2021

More Information

Terms related to this study

• Keywords: Glycemic index; Postprandial hyperglycemia; Anthocyanin; Black rice
• Additional Relevant MeSH Terms: Metabolic Diseases; Glucose Metabolism Disorders; Hyperglycemia
• Other Study ID Numbers: H-17-064

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No