Biomarkers of Whole Grain Wheat and Rye Intake

Urinary Alkylresorcinol Metabolites as a Biomarker of Whole Grain Wheat and Rye Intake

Alkylresorcinols (AR) are a group of lipids found in the bran fraction of wheat and rye grains. AR are absorbed into the bloodstream and their metabolites are excreted in urine in measurable amounts following ingestion of wholegrain (WG) wheat or rye cereal. As AR are absent in refined cereals, plasma AR and urinary AR metabolites are proposed as suitable biomarkers of dietary intake of WG wheat and rye cereal, with a number of studies supporting this proposal. Different AR species are present in characteristic quantities in WG wheat in comparison to WG rye cereals, which can allow identification of the main source of WG (wheat or rye) in individuals by analysing the AR concentrations in blood. However the patterns of urinary AR metabolite excretion following wheat or rye intake have not yet been investigated to determine if there are differences according to WG source.

The present study aims to:

(i) investigate the differences in AR metabolite excretion pattern in spot and 24 hour urine samples after following a predominantly WG rye-based diet in comparison to a predominantly WG wheat-based diet and in comparison to control (refined cereal diet) (ii) compare the validity and reproducibility of AR metabolites in spot urine samples in comparison to 24 hour urine samples.

Study Overview

• Status: Completed
• Conditions: Healthy Volunteers
• Intervention / Treatment: Other: Whole grain rye; Other: Refined cereal; Other: Whole grain wheat

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • London, United Kingdom, SW1 9NH
    • Diabetes and Nutritional Sciences Division, King's College London

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Body mass intake 18.5-30.0 kg/m2
• Weight stable for 2 months
• Generally healthy

Exclusion Criteria:

• Previous or current chronic disease including heart disease, diabetes, gastrointestinal, liver, renal or endocrine disorders
• Drug or alcohol misuse in the last year
• Current pregnancy or lactation
• Weight change of >3 kg in the last two months
• Current regular user of certain prescription medications (except contraceptives)
• Unwilling to consume or to stop consuming WG wheat, WG rye or refined cereals
• Unwilling to discontinue multivitamins/dietary supplements during study

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Whole grain rye; 3-4 portions per day of WG rye containing foods (approximately 20 WG per portion)	Other: Whole grain rye; Other: Refined cereal
Experimental: Whole grain wheat; 3-4 portions per day of WG wheat containing foods (approximately 20 WG per portion)	Other: Refined cereal; Other: Whole grain wheat
Placebo Comparator: Refined cereal; No intake of WG wheat or WG rye cereals, only refined cereals or non-AR containing WG cereals (e.g. WG rice or oats)	Other: Refined cereal

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
24-h urinary DHBA:DHPPA ratio	DHBA: 3,5-dihydroxybenzoic acid DHPPA: 3-(3,5-dihydroxyphenyl)-propanoic acid DHBA & DHPPA are the main AR metabolites excreted in urine	Endpoint (Day 3)

Secondary Outcome Measures

Outcome Measure	Time Frame
DHBA:DHPPA ratio in morning spot urine	Endpoint (Day 3)
Total 24-h urinary AR metabolite (DHBA + DHPPA) excretion	Endpoint (Day 3)
Total 24-h urinary DHBA excretion	Endpoint (Day 3)
Total 24-h urinary DHPPA excretion	Endpoint (Day 3)
24-h urinary total AR (DHBA+DHPPA):creatinine ratio	Endpoint (Day 3)
24-h urinary DHBA:creatinine ratio	Endpoint (Day 3)
24-h urinary DHPPA:creatinine ratio	Endpoint (Day 3)
Total AR (DHBA+DHPPA):creatinine ratio in morning spot urine sample	Endpoint (Day 3)
DHBA:creatinine ratio in morning spot urine sample	Endpoint (Day 3)
DHPPA:creatinine ratio in morning spot urine sample	Endpoint (Day 3)

Other Outcome Measures

Outcome Measure	Time Frame
Estimated daily intake of WG wheat and rye cereals	Assessed throughout each intervention period (Days 1-3)

Collaborators and Investigators

• Sponsor: King's College London
• Investigators: Principal Investigator: Julia Darzi, PhD, King's College London

Study record dates

Study Major Dates

• Study Start: May 1, 2014
• Primary Completion (Actual): September 1, 2014
• Study Completion (Actual): September 1, 2014

Study Registration Dates

• First Submitted: May 29, 2014
• First Submitted That Met QC Criteria: June 2, 2014
• First Posted (Estimate): June 4, 2014

Study Record Updates

• Last Update Posted (Estimate): March 6, 2015
• Last Update Submitted That Met QC Criteria: March 5, 2015
• Last Verified: March 1, 2015

More Information

Terms related to this study

• Keywords: Urine; Dietary assessment; Rye; Whole grain; Wheat; Nutritional biomarker; Alkylresorcinol
• Other Study ID Numbers: BDM/13/14-78