The Impact of Dietary Flavanols on the Gut Microflora

Sponsor

University of Reading (Other)

Overall Status

Completed

CT.gov ID

NCT01091922

Collaborator

(none)

Enrollment

Location

Arms

Duration (Months)

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The primary propose of this study is to determine the impact of flavanol-rich cocoa on the growth of the human gut microbiota.

Condition or Disease	Intervention/Treatment	Phase
Intestinal Bacteria Growth	Dietary Supplement: Low flavanol cocoa beverage Dietary Supplement: High flavanol cocoa beverage	N/A

Detailed Description

A randomised, placebo-controlled, double-blind, cross-over human intervention study will be conducted in 20 healthy human volunteers to test the impact of a high-flavanol containing meal on the growth of the large intestinal bacteria (microflora). The high flavanol test meal will contain 495 mg of flavanols and the low flavanol control will contain 23 mg of flavanols. The two intervention diets are otherwise matched for macro- and micronutrient content. Changes in the gut microbiota will be determined by measuring bacterial population levels in human faecal material using 16S rRNA targeted oligonucleotide probes and fluorescence in situ hybridization. A number of other biochemical and physiological measures will be recorded including blood glucose, lipoproteins, cytokine levels and blood pressure.

Study Design

Study Type:

Interventional

Actual Enrollment :

22 participants

Allocation:

Randomized

Intervention Model:

Crossover Assignment

Masking:

Double (Participant, Investigator)

Primary Purpose:

Basic Science

Official Title:

Prebiotic Evaluation of Cocoa-derived Flavanols in Healthy Humans Using a Randomized, Double Blind, Crossover, Placebo-controlled Intervention Study

Study Start Date :

Jan 1, 2008

Actual Primary Completion Date :

Dec 1, 2009

Actual Study Completion Date :

Dec 1, 2009

Arms and Interventions

Arm	Intervention/Treatment
Placebo Comparator: Low Flavanol Low flavanol drink containing 23 mg of total flavanols. Macro- and micro-nutrient matched with active comparator	Dietary Supplement: Low flavanol cocoa beverage 23 mg of total flavanols from cocoa
Active Comparator: High Flavanols High Flavanol drink containing 495 mg of total flavanols	Dietary Supplement: High flavanol cocoa beverage 495 mg of total flavanols from cocoa

Arm

Intervention/Treatment

Placebo Comparator: Low Flavanol

Low flavanol drink containing 23 mg of total flavanols. Macro- and micro-nutrient matched with active comparator

Dietary Supplement: Low flavanol cocoa beverage

23 mg of total flavanols from cocoa

Active Comparator: High Flavanols

High Flavanol drink containing 495 mg of total flavanols

Dietary Supplement: High flavanol cocoa beverage

495 mg of total flavanols from cocoa

Outcome Measures

Primary Outcome Measures

Faecal bacteria numbers using 16S rRNA targeted oligonucleotide probes analysis and fluorescence in situ hybridization [baseline and 4 weeks]
Measurements of the growth rate and number of bacterial species in human faecal samples using 16S rRNA targeted oligonucleotide probes and fluorescence in situ hybridisation.

Secondary Outcome Measures

Blood pressure [Baseline, 4 weeks]

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 50 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

a signed consent form
age of 18-50 years inclusive
BMI between 20-26

Exclusion Criteria:

pregnant or lactating
allergy to milk products
sensitivity to alkaloids and/or caffeine
gastrointestinal disorders (e.g., chronic constipation, diarrhoea, inflammatory bowel disease, -inflammatory bowel syndrome, or other chronic gastrointestinal complaints)
diabetes mellitus
hypertension (>150/90 mm/Hg)
anaemia and gall bladder problems
not consuming probiotics, prebiotics, antibiotics or anti-inflammatory or blood lowering medication within a 2-month period prior to the study.

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	University of Reading	Reading	Berkshire	United Kingdom	RG2 9AR

Sponsors and Collaborators

University of Reading

Investigators

Principal Investigator: Jeremy Spencer, PhD, University of Reading

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

Responsible Party:

, ,

ClinicalTrials.gov Identifier:

NCT01091922

Other Study ID Numbers:

UReading-2009-01

First Posted:

Mar 24, 2010

Last Update Posted:

Mar 24, 2010

Last Verified:

Mar 1, 2008

Keywords provided by , ,

flavonoids

flavanols

bacteria

Study Results

No Results Posted as of Mar 24, 2010