Effects of Blueberry on Gut Microbiota and Metabolic Syndrome

Prebiotic Effects of Blueberry in Overweight/Obese Individuals: Potential Role of the Gut Microbiota in Alleviating the Metabolic Syndrome.

There is growing evidence that nutritional intervention with dietary polyphenols can positively modulate the gut microbiota to improve cardiometabolic health. Whether the beneficial effects of blueberries on obesity and the metabolic syndrome can be linked to their potential impact on the gut microbiota and intestinal integrity remains speculative at this time. Moreover, the mechanisms of action underlying health benefits associated to blueberry consumption are still unknown. The investigators are thus proposing to combine the study of metagenomics, transcriptomics and metabolomics to test whether a prebiotic activity of highbush blueberries can play a role in the prevention of obesity-linked metabolic syndrome in a clinical setting.

Study Overview

• Status: Active, not recruiting
• Conditions: Metabolic Syndrome; Gut Microbiota
• Intervention / Treatment: Dietary supplement: 50 g of blueberry powder, taken daily for 8 weeks; Dietary supplement: 50g of placebo blueberry powder, taken daily for 8 weeks

• Study Type: Interventional
• Enrollment (Actual): 59
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Québec, Canada, G1V0A6
    • Laval University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 55 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Men and premenopause women in good health
• Caucasians
• At least one of the following : BMI between 25 and 40 kg/m2 or Waist circumference ≥ 80 cm for women and ≥ 94 cm for men
• At least one of the following : TG ≥ 1.35 mmol/L or fasting insulinemia ≥ 42 pmol/L

Exclusion Criteria:

• Metabolic disorders (hypertension, diabetes, hypercholesterolemia)
• Regular use of medication affecting study parameters
• Use of natural health product in the last 3 months
• Use of antibiotics in the last 3 months
• Nicotine users
• Allergy or intolerance for blueberries
• Blueberry taste aversion
• More than 2 alcohol drinks par day
• Particular dietary habits (vegetarism, gluten-free diet, cetogenic diet...)
• Weight change of more than 5% in the last 3 months
• Surgery in the last 3 months or planed during the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Blueberry powder	Dietary supplement: 50 g of blueberry powder, taken daily for 8 weeks; Subjects will consume blueberry powder during 8 weeks to test the possible effects of blueberries on gut microbiota composition and on metabolic syndrome parameters.
Placebo Comparator: Blueberry placebo powder	Dietary supplement: 50g of placebo blueberry powder, taken daily for 8 weeks; Subjects will consume blueberry placebo powder to test if there is a significant difference on the impact on gut microbiota composition and metabolic syndrome parameters between this treatment and the active treatment (blueberry powder).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Changes in plasma insulin/glucose of overweight/obese men and women taking either blueberry powder or placebo blueberry powder	12 months
Changes in plasma lipids/lipoproteins of overweight/obese men and women taking either blueberry powder or placebo blueberry powder	12 months

Secondary Outcome Measures

Outcome Measure	Time Frame
Changes in gene expression in overweight/obese men and women taking either blueberry powder or placebo blueberry powder	3-6 months
Changes in metabolites concentration in overweight/obese men and women taking either blueberry powder or placebo blueberry powder	3-6 months
Changes in the gut microbiota composition in overweight/obese men and women taking either blueberry powder or placebo blueberry powder	3-6 months
Changes in blood pressure of overweight/obese men and women taking either blueberry powder or placebo blueberry powder	12 months
Changes in intestinal integrity of overweight/obese men and women taking either blueberry powder or placebo blueberry powder	12 months
Changes in inflammation biomarkers of overweight/obese men and women taking either blueberry powder or placebo blueberry powder	12 months

Collaborators and Investigators

• Sponsor: Laval University
• Investigators: Principal Investigator: Marie-Claude Vohl, Laval University

Publications and helpful links

General Publications

• Rousseau M, Horne J, Guenard F, de Toro-Martin J, Garneau V, Guay V, Kearney M, Pilon G, Roy D, Couture P, Couillard C, Marette A, Vohl MC. An 8-week freeze-dried blueberry supplement impacts immune-related pathways: a randomized, double-blind placebo-controlled trial. Genes Nutr. 2021 May 17;16(1):7. doi: 10.1186/s12263-021-00688-2.

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2017
• Primary Completion (Actual): January 14, 2019
• Study Completion (Estimated): December 1, 2025

Study Registration Dates

• First Submitted: July 6, 2017
• First Submitted That Met QC Criteria: August 28, 2017
• First Posted (Actual): August 29, 2017

Study Record Updates

• Last Update Posted (Actual): October 3, 2023
• Last Update Submitted That Met QC Criteria: October 2, 2023
• Last Verified: October 1, 2023

More Information

Terms related to this study

• Keywords: Diet; Blueberry
• Additional Relevant MeSH Terms: Pathologic Processes; Glucose Metabolism Disorders; Metabolic Diseases; Disease; Insulin Resistance; Hyperinsulinism; Syndrome; Metabolic Syndrome
• Other Study ID Numbers: BLEUET 2017-135

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No