Impact of Blueberry Consumption on Gastrointestinal Health

Impact of Blueberry Consumption on Intestinal Permeability, Gut Microbiota, and Gut-Derived Inflammation in Individuals With Elevated Risk of a Pro-Inflammatory Gut Milieu

This study will evaluate the impact of blueberry consumption on markers of gastrointestinal health including gut microbiota, intestinal permeability, and gut-derived inflammation in those vulnerable to a unhealthy gut milieu. All participants will consume a blueberry powder and a placebo in this crossover study.

Study Overview

• Status: Completed
• Conditions: Obesity; Circadian Dysregulation
• Intervention / Treatment: Dietary supplement: Blueberry powder; Dietary supplement: Placebo powder

Detailed Description

The commensal bacteria that reside in the human gut, known as the gut microbiota, is a complex system that modulates local gut homeostasis and systemic biological processes. Several environmental factors have been shown to influence the gut milieu (including microbiota), and thus both gastrointestinal and host health. Relevant to the current proposal is the influence of body weight, diet, and circadian rhythms. In the current study, the investigators propose to use these common disruptors of gastrointestinal health through recruiting obese shift workers with a low-fiber diet to identify if these disrupted individuals can benefit from blueberry intake. Specifically, the study objectives are to determine if 24 g whole blueberry powder consumed daily can beneficially modify intestinal permeability, gut microbiota, microbial metabolites, and both gut-derived and systemic inflammation in those most susceptible to a pro-inflammatory milieu. This will be accomplished through a 14-week crossover study in which 28 individuals will be randomized by treatment group order to 4 weeks of whole blueberry powder and placebo powder, with a 4-week wash out in between the treatment periods.

• Study Type: Interventional
• Enrollment (Actual): 28
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Nebraska
    • Lincoln, Nebraska, United States, 68132
      • University of Nebraska
    • Omaha, Nebraska, United States, 68198
      • University of Nebraska Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 19 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• obese (BMI +/- 30.0 kg/m2)
• shift workers (shift work overnight (third shift) +/= 3 days/week for the past 3 months)
• 19-70 years of age

Exclusion Criteria:

• patient history of gastrointestinal diseases except for hiatal hernia, GERD, or hemorrhoids, mild gastrointestinal symptoms
• elevated laboratory values from a comprehensive metabolic panel (CMP) and complete blood count (CBC) with the exception of glucose (+/= 126 mg/dL; if elevated, confirmed with HA1c of greater than or equal to 6.5%) and ALT, AST, or ALP over 2 times normal levels (to allow for mild elevations resulting from fatty liver often seen in obese) unless approved by study physician
• currently pregnant or plans to become pregnant during the study as determined by participant report
• antibiotic use within the last 12 weeks prior to enrollment
• presence of chronic metabolic disease (e.g., cardiovascular disease, diabetes, cancer) or per physician discretion
• recent (past 4 weeks) major change in dietary habits or a plan to have a major change in dietary habits during the study
• habitual blueberry consumption of more than 0.5 cups 2x/week or a 4-week washout period if consumes
• allergy or intolerance to blueberries
• consumption of supplemental fiber, probiotics or prebiotics without an appropriate 4-week washout period
• restrictive dietary patterns (e.g., ketogenic, Paleolithic) or a diet high in fiber (+/= 14 g/1000 kilocalories) to increase study result generalizability to the U.S. population (low-fiber diet), as well as provide another stimuli for gut leakiness
• unwillingness to consent to the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Blueberry powder; 4 weeks of supplementation of 24 g whole blueberry powder	Dietary supplement: Blueberry powder; Dried, powdered blueberries will be consumed at 24 g/day in two divided doses at least 4 hours apart.
Placebo Comparator: Placebo powder; 4 weeks of supplementation of 24 g placebo powder (maltodextrin)	Dietary supplement: Placebo powder; A placebo consisting maltodextrin will be consumed at 24 g/day in two divided doses at least 4 hours apart.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
intestinal permeability	urinary sugar measurement by gas chromatography (GC): Sucralose, lactulose, mannitol, sucrose as a percent of oral dose.	28 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Microbiota	Microbiota composition through shotgun sequencing. Composition includes relative abundance of all microbes in stool.	28 days
Microbial metabolites	Quantity of stool short-chain fatty acid (butyrate, propionate, acetate) per dry stool weight by gas chromatography	28 days
Gut-derived/systemic inflammation	Concentration of serum lipopolysaccharide (LPS), LPS-binding protein (LBP), and interleukin-6 (IL6)	28 days

Collaborators and Investigators

• Sponsor: University of Nebraska Lincoln
• Collaborators: Rush University Medical Center; University of Nebraska
• Investigators: Principal Investigator: Heather E Rasmussen, PhD, University of Nebraska Lincoln

Study record dates

Study Major Dates

• Study Start (Actual): March 26, 2019
• Primary Completion (Actual): March 2, 2023
• Study Completion (Actual): March 2, 2023

Study Registration Dates

• First Submitted: April 15, 2019
• First Submitted That Met QC Criteria: April 28, 2019
• First Posted (Actual): May 1, 2019

Study Record Updates

• Last Update Posted (Actual): March 22, 2023
• Last Update Submitted That Met QC Criteria: March 20, 2023
• Last Verified: March 1, 2023

More Information

Terms related to this study

• Keywords: Microbiota; Intestinal permeability; Blueberry
• Additional Relevant MeSH Terms: Nervous System Diseases; Chronobiology Disorders
• Other Study ID Numbers: 18557

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