A Study on Gastrointestinal Transit Time at the Population Level

NCT07309250 | Not Yet Recruiting

• 1 other identifier: S70908
• Study Type: observational
• Target: 932
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this study is to investigate the baseline of gastrointestinal transit time (GITT) and explore its relationship with other health indicators in 932 healthy adult volunteers. The main questions it aims to answer are: What are the population-level baseline values for GITT using the blue dye method? How is GITT associated with key physiological parameters including blood metabolic markers, life style, and stool characteristics? Participants will: Consume a standardized blue dye muffin after overnight fasting at the research center; Offer a finger prock blood samples for metabolic profiling; Collect stool samples for moisture measurement; Complete detailed questionnaires on diet, lifestyle, and bowel habits; Record the time of first blue stool appearance to determine GITT.

Conditions

Gastrointestinal Transit Time

Keywords

Gastrointestinal motility; Baseline study; Reference value

Outcome Measures

Primary Outcomes (1)

• Gastrointestinal transit time

  Calculate the transit time by the recorded muffin consuming time, first blue stool appearance time and last blue stool appearance time

  From enrollment to the end of study at 2 weeks

Secondary Outcomes (17)

• Height (cm)

  baseline

• Weight (kg)

  baseline

• BMI

  baseline

• Blood glucose (mmol/L)

  baseline

• Fat mass (kg)

  baseline

Study Arms (1)

Adult participants

Healthy adult participants without serious gastrointestinal diseases

Other: Diet

Interventions

Diet OTHER

Participants will consume a regular muffin containing blue dye

Adult participants

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Healthy volunteers from the Flanders region who volunteered to participate in the research

You may qualify if:

• years old
• kg/m² ≤ BMI ≤ 25 kg/m² or BMI ≥ 30 kg/m² (people with normal weight or obesity)
• Provision of informed consent to participate.

You may not qualify if:

• Gastrointestinal conditions which may affect nutrient absorption or gastric emptying, including coeliac disease, Crohn's disease, previous resection of the small intestine other than bariatric surgery, gastroparesis;
• Using medications which effect gastric motility (e.g., domperidone, erythromycin, metoclopramide, prucalopride, opiates, loperamide, …)
• The ingredients of blue muffins include gluten, nuts, baking powder, sugar, vanilla extract and sunflower oil. Participants with allergies to these ingredients;
• Current diagnosis of cancer;
• Advanced organ failure, including chronic kidney disease Stage 5, liver cirrhosis Child-Pugh B or C, intestinal failure, heart failure stage D, or chronic obstructive pulmonary disease stage 4;
• Immobility;
• Neuromuscular degenerative conditions associated with muscular atrophy, such as myasthenia gravis, muscular dystrophies, fibromyalgia, or multiple Sclerosis;

Sponsors & Collaborators

• KU Leuven: lead

Study Sites (1)

Department of Chronic Diseases and Metabolism

Leuven, Flemish Brabant, 3000, Belgium

Location

MeSH Terms

Interventions

Diet

Intervention Hierarchy (Ancestors)

Nutritional Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena

Central Study Contacts

Christophe Matthys

CONTACT

+32 016342655; christophe.matthys@uzleuven.be

Wei Li

CONTACT

+32 016344539; wei.li2@kuleuven.be

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Target Duration: 5 Days
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: November 17, 2025
• First Posted: December 30, 2025
• Study Start: December 1, 2025
• Primary Completion (Estimated): December 30, 2026
• Study Completion (Estimated): December 30, 2026
• Last Updated: December 30, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

BE (1)