Impact of Dairy Integration Into Canadian Food Guide on Gut Health (GutMilk)

The primary objective is to investigate the impact of milk, fermented milk, and soy beverages, incorporated in a diet reflecting adherence to Canadian food guide recommendations on food choices on gut microbiota in middle-aged adults (45-65 years) with abdominal obesity and slightly deteriorated lipids and/or glucose profile. The study aims to discern whether the integration of soy beverages (control), milk, and fermented milk within the CFG diet contributes to distinct gut outcomes and alterations in gut health. We hypothesized that milk and fermented milk will further promote beneficial changes in gut health parameters including gut microbiota composition, trans-epithelial permeability, and inflammation, relative to soy beverages.

Study Overview

• Status: Recruiting
• Conditions: Gut Epithelial Permeability; Gut Microbiota Composition and Diversity; Gut and Circulating Inflammatory Markers; Milk and Digestion
• Intervention / Treatment: Other: Milk; Other: Fermented milk; Other: Soy beverage

Detailed Description

Single-blinded crossover RCT to test the impact of integrating dairy (i.e., milk and fermented milk) into the Canadian Food Guide (CFG) diet on gut health, in fully controlled dietary settings. The trial will include mid-age women and men with abdominal obesity and slightly deteriorated metabolic profile (n=20). The trial will feature 3 controlled-feeding phases (14 days), allocated in a random order and separated by free-uncontrolled feeding washout periods (14-28 days). Each dietary intervention phase will be initiated by a Run-in full-feeding period (4 days), to standardize participants' dietary intakes, and immediately followed by one of the 3 dietary interventions (9 days) reflecting adherence to the CFG recommendation (9 days, CFG-Diet) incorporating either soy beverages (Control), milk, or non-effervescent fermented milk.

This approach was shown to be highly informative in deciphering the interaction between diet and the gut microbiota in previous work. It will be able to assess how integrating dairy (i.e., milk and fermented milk) into the Canadian Food Guide (CFG) diet promptly modulates gut health parameters (i.e. gut microbiota composition, inflammatory states, and gut permeability) in the context of obesity and metabolic complications, relative to a plant-based alternative. The fully controlled dietary setting of this study design will provide precise intakes of foods and bioactive nutrients, which will enable us to comprehensively assess the impact of dairies on gut health.

The trial will include 10 women and 10 men with abdominal obesity and slightly deteriorated metabolic profile.

Diet sequence allocation will be randomized with a sex-specific stratification. The study will be single-blinded, such as participants will not be informed of the precise nature of the diet sequence.

TRIAL INTERVENTION PHASES (3 X 14 DAYS)

During each intervention phases, all meals and foods will be provided to ensure optimal diet control. Each intervention phases will follow this sequence:

• Day 0: Initiation of the run-in full-feeding period (4 days) to standardize participants' dietary intakes.
• Day 4: Baseline sampling and data collection.
• Day 4: Initiation of the CFG dietary intervention (10 days) incorporating either soy beverages (Control), milk, or non-effervescent fermented milk.
• Day 6: Post-intervention (+2 days) sampling and data collection.
• Day 13: Post-intervention (+9 days) sampling and data collection. End of the intervention phases.

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Alain Veilleux, PhD; Phone Number: 405108 418 656-2131; Email: alain.veilleux@fsaa.ulaval.ca

Study Locations

• Canada
  • Quebec
    • Québec, Quebec, Canada, G1V 0A6
      • Recruiting
      • Institute of Nutrition and Functional Foods (INAF)
      • Contact: Alain Veilleux, PhD; Phone Number: 405108 418 656 2131; Email: alain.veilleux@fsaa.ulaval.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• IMC < 45
• Waist circumference > 80 cm (Women) or 94 cm (men)

Exclusion Criteria:

• History of diabetes (types 1 and 2), CVD, enteropathy, immune diseases or bariatric surgery
• Cancer (diagnostic and/or treatment) during the last 5 years
• Antibiotic consumption during the last 3 months
• Active smoking or cannabis consumption
• Lactose intolerance or allergy, any allergies to foods given in the intervention phases
• Irregular defecation patterns
• Pregnancy/lactation
• Inability to speak French

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Milk; - Consumption of milk 3 times per day during 9 days alongside CFG diet, following a 4 day control diet	Other: Milk; Consumption of 1 cup milk 3 times per day during 9 days alongside CFG diet; Other: Fermented milk; Consumption of fermented milk 3 times per day during 9 days alongside CFG diet; Other: Soy beverage; Consumption of a soy beverage 3 times per day during 9 days alongside CFG diet
Experimental: Fermented milk; - Consumption of fermented milk 3 times per day during 9 days alongside CFG diet, following a 4 day control diet	Other: Milk; Consumption of 1 cup milk 3 times per day during 9 days alongside CFG diet; Other: Fermented milk; Consumption of fermented milk 3 times per day during 9 days alongside CFG diet; Other: Soy beverage; Consumption of a soy beverage 3 times per day during 9 days alongside CFG diet
Experimental: Soy beverage; - Consumption of a soy beverage 3 times per day during 9 days alongside CFG diet, following a 4 day control diet	Other: Milk; Consumption of 1 cup milk 3 times per day during 9 days alongside CFG diet; Other: Fermented milk; Consumption of fermented milk 3 times per day during 9 days alongside CFG diet; Other: Soy beverage; Consumption of a soy beverage 3 times per day during 9 days alongside CFG diet

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gut epithelial permeability	Post-intervention lactulose/mannitol ratio by LCMS, 0-5 hours after ingestion of the non-metabolizable sugar	This outcome will be measured on the last day (day 13) of each intervention phase.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gut inflammatory markers	Fecal calprotectin levels by ELISA	Samples will be collected on days 6 and 13 of each intervention phase.
Perceived gut symptoms	Perception gastrointestinal symptoms questionnaires	Gastrointestinal symptoms questionnaire is administered on days 0, 4 and 13.
Whole gut transit time	Whole gut transit time (h) by the Blue poop challenge	At days 1, 4 and 11.

Collaborators and Investigators

• Sponsor: Laval University
• Investigators: Principal Investigator: Alain Veilleux, PhD, Laval University

Study record dates

Study Major Dates

• Study Start (Actual): October 6, 2025
• Primary Completion (Estimated): August 31, 2026
• Study Completion (Estimated): August 31, 2026

Study Registration Dates

• First Submitted: September 22, 2025
• First Submitted That Met QC Criteria: December 1, 2025
• First Posted (Actual): December 2, 2025

Study Record Updates

• Last Update Posted (Actual): December 2, 2025
• Last Update Submitted That Met QC Criteria: December 1, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Inflammation; Gut microbiota; Milk consumption; Gut epithelial permeability
• Additional Relevant MeSH Terms: Pathologic Processes; Pathological Conditions, Signs and Symptoms; Inflammation; Food; Diet, Food, and Nutrition; Physiological Phenomena; Food and Beverages; Beverages; Fermented Foods; Dairy Products; Milk Substitutes; Soy Foods; Vegetable Products; Vegetables; Milk; Cultured Milk Products; Soy Milk
• Other Study ID Numbers: 2024-569

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: All IPD that underlie results in a publication

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No