Measuring the Glycemic Index and Tracking Metabolites of New and Emerging Lentil Varieties

NCT ID: NCT02909803

Last Updated: 2016-09-21

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 10 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2013-01-31
• Study Completion Date: 2016-07-31

Brief Summary

It is not known whether different lentil varieties have the same efficacy in lowering blood glucose. Similarly, the carbohydrate component of lentils responsible for lowering blood glucose is not known, nor is the bioavailability of lentil metabolites and polyphenol bioactive.

Detailed Description

The overall aim of this work is to produce credible evidence for substantiating a food health claim for post prandial blood glucose lowering by lentil. Although several studies have shown that lentil consumption results in a lowering of post prandial blood glucose, it is not known whether different lentil varieties have the same efficacy. Similarly, the carbohydrate component of lentils responsible for lowering blood glucose is not known, nor is the bioavailability of lentil metabolites and polyphenol bioactive. The investigators hypothesize that the slowly digestible starch content of lentil is inversely related to in vivo glycemic response. The specific aims of this study are: (i) to identify the putative component(s) in lentil that might account for its blood glucose lowering effect, and (ii) to identify differences in blood glucose reduction among lentil varieties. These aims will be achieved in a three-step process. Firstly, in vitro studies will be pursued to determine the carbohydrate fractions of 20 new and emerging Canadian lentil varieties. Secondly, these results will be used to choose 8 lentil varieties with different slowly digestible starch content for a human Glycemic Index study. Thirdly, identification of lentil metabolites will be achieved by collecting extra capillary blood (200uL)and urine samples at fasting and 120min for measurement of polyphenols and metabolites using established HPLC and metabolomics techniques.

Conditions

Hyperglycemia; Dietary Modification

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Lentil Variety

Each participant will consume a serving of one of eight lentil varieties (Greenland; Improve; Impower; Imigreen; Asterix; Redberry; Redcliff; Redbow) containing 25g available carbohydrate at separate study visits

Group Type: EXPERIMENTAL

Lentil Variety

Intervention Type: OTHER

Participants will consume 8 varieties of lentils that are cooked by boiling

White Bread

Each participant will consume a serving of white bread containing 25g available carbohydrate on two separate visits

Group Type: ACTIVE_COMPARATOR

White Bread

Intervention Type: OTHER

Participants will consume white bread on at least two different test days

Interventions

Lentil Variety

Participants will consume 8 varieties of lentils that are cooked by boiling

Intervention Type: OTHER

White Bread

Participants will consume white bread on at least two different test days

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Male or non-pregnant females, 18-75 years of age, inclusive
• Body mass index (BMI) < 40 kg/m²
• Willing to maintain habitual diet, physical activity pattern, and body weight throughout the trial and to refrain from smoking for 12hr prior to each visit.
• Normal fasting serum glucose (<7.0mmol/L capillary corresponding to whole blood glucose <6.3mmol/L).
• Understanding the study procedures and willing to provide informed consent to participate in the study and authorization to release relevant protected health information to the study investigator.

• Known history of AIDS, hepatitis, diabetes or a heart condition
• Subjects using medications or with any condition which might, in the opinion of Dr. Wolever, the Medical Director of GI Labs, either: 1) make participation dangerous to the subject or to others, or 2) affect the results.
• Major trauma or surgical event within 3 months of screening.
• Unwillingness or inability to comply with the experimental procedures and to follow GI Labs safety guidelines.
• Known intolerance, sensitivity or allergy to any ingredients in the study products.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 75 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Glycemic Index Laboratories, Inc

INDUSTRY

Sponsor Role: collaborator

University of Manitoba

OTHER

Sponsor Role: collaborator

Guelph Food Research Centre

OTHER_GOV

Sponsor Role: lead

Responsible Party

Dan Ramdath

Research Scientist

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Dan Ramdath, PhD

Role: PRINCIPAL_INVESTIGATOR

Guelph Research and Development Centre

Locations

Glycemic Index Laboratories, Inc

Toronto, Ontario, Canada

Countries

Canada

References

Health Canada. Bureau of Nutritional Sciences, food directorate, health products and food branch. June 2013. Draft guidance document on food health claims related to the reduction in post-prandial glycaemic response

Reference Type: BACKGROUND

Wolever TM, Jenkins DJ. The use of the glycemic index in predicting the blood glucose response to mixed meals. Am J Clin Nutr. 1986 Jan;43(1):167-72. doi: 10.1093/ajcn/43.1.167.

Reference Type: BACKGROUND

PMID: 3942088 (View on PubMed)

Wolever TMS (2006). The Glycaemic Index: A Physiological Classification of Dietary Carbohydrate. CABI Publishing, Wallingford, UK.

Reference Type: BACKGROUND

Ramdath D, Renwick S, Duncan AM. The Role of Pulses in the Dietary Management of Diabetes. Can J Diabetes. 2016 Aug;40(4):355-63. doi: 10.1016/j.jcjd.2016.05.015.

Reference Type: BACKGROUND

PMID: 27497151 (View on PubMed)

Wang, L., Zahradka, P., Taylor, C. and Aliani, M., Metabolomics Analysis of Serum and Urine After Bean Consumption by Patients with Peripheral Arterial Disease. The FASEB Journal, 30(1 Supplement): 682-10, 2016.

Reference Type: BACKGROUND

Other Identifiers

Lentil metabolites

Identifier Type: -

Identifier Source: org_study_id