Recruiting

Gastrointestinal Responses to Dietary Fibers in Adults on Weight Loss Medications

0 criteria met from your profileSee at a glance how your profile meets each eligibility criteria.
What is being tested

High Fiber Bar with Inulin

+ High Fiber bar with Fiber Blend
+ High Fiber Bar with Resistant Starch type 4
Other
Who is being recruted

Body Weight

+ Body Weight Changes
+ Weight Loss
From 25 to 64 Years
See all eligibility criteria
How is the trial designed

Other Study

Placebo-Controlled
Interventional
Study Start: May 2025
See protocol details

Summary

Principal SponsorMidwest Center for Metabolic and Cardiovascular Research
Study ContactCaryn G Adams, MPH
Last updated: December 11, 2025
Sourced from a government-validated database.Claim as a partner
Study start date: May 29, 2025Actual date on which the first participant was enrolled.

This study explores how different snack bars containing fiber affect the digestive system of adults who are taking GLP-1 agonists, which are medications often used for weight loss. The study aims to understand the gastrointestinal reactions people experience when consuming these fiber-rich snack bars compared to a regular snack bar. This research is important because it might help improve dietary recommendations for those using weight loss medications by identifying which types of snack bars could be more comfortable or beneficial for them. Participants in this study will be asked to eat three different kinds of fiber-containing snack bars and one regular snack bar over separate 7-day periods. During each period, participants will report any gastrointestinal symptoms they experience, allowing researchers to compare the different effects of each bar. This study does not mention specific risks, but it focuses on understanding the digestive responses to fibers, which could lead to better dietary guidance for people on GLP-1 agonists.

Official TitleA Randomized, Double-Blind Crossover Trial to Assess Gastrointestinal Responses to Dietary Fibers in Adults Using Weight Loss Medications 
Principal SponsorMidwest Center for Metabolic and Cardiovascular Research
Study ContactCaryn G Adams, MPH
Last updated: December 11, 2025
Sourced from a government-validated database.Claim as a partner

Protocol

This section provides details of the study plan, including how the study is designed and what the study is measuring.
Design Details
50 patients to be enrolledTotal number of participants that the clinical trial aims to recruit.
Other Study
Some studies explore topics that don't fall into a specific category. These might include innovative research, new technologies, or emerging healthcare areas.

How participants are assigned to different groups/arms
In this clinical study, participants are placed into groups randomly, like flipping a coin. This ensures that the study is fair and unbiased, making the results more reliable. By assigning participants by chance, researchers can better compare treatments without external influences.

Other Ways to Assign Participants
Non-randomized allocation
: Participants are assigned based on specific factors, such as their medical condition or a doctor's decision.

None (Single-arm trial)
: If the study has only one group, all participants receive the same treatment, and no allocation is needed.

How treatments are given to participants
Participants receive different treatments one after the other, switching from one to another during the study. This helps researchers understand how individuals respond to multiple treatments.

Other Ways to Assign Treatments
Single-group assignment
: Everyone gets the same treatment.

Parallel assignment
: Participants are split into separate groups, each receiving a different treatment.

Factorial assignment
: Participants receive different combinations of treatments.

Sequential assignment
: Participants receive treatments one after another in a specific order, possibly based on individual responses.

Other assignment
: Treatment assignment does not follow a standard or predefined design.

How the effectiveness of the treatment is controlled
In a placebo-controlled study, some participants receive the experimental treatment, while others receive an inert substance (placebo) to compare outcomes. This method helps to isolate the effect of the treatment from the psychological effects of receiving any treatment at all.

Other Options
Non-placebo-controlled
: No placebo is used. All participants receive the actual treatment or alternative interventions (often the Standard of Care), and comparisons are made between these treatments.

How the interventions assigned to participants is kept confidential
Participants, researchers, outcome assessors, and care providers do not know which treatment is being given. This is the most complete way to prevent bias and keep the study as neutral as possible.

Other Ways to Mask Information
Open-label
: Everyone knows which treatment is being given.

Single-blind
: Participants do not know which treatment they are receiving, but researchers do.

Double-blind
: Neither participants nor researchers know which treatment is given.

Triple-blind
: Participants, researchers, and outcome assessors do not know which treatment is given.

Eligibility

Researchers look for people who fit a certain description, called eligibility criteria: person's general health condition or prior treatments.
Conditions
Criteria
Any sexBiological sex of participants that are eligible to enroll.
From 25 to 64 YearsRange of ages for which participants are eligible to join.
Healthy volunteers allowedIf individuals who are healthy and do not have the condition being studied can participate.
Conditions
Pathology
Body Weight
Body Weight Changes
Weight Loss
Criteria

Inclusion Criteria: 1. Male or female 25 to 64 years of age, inclusive. There will be approximately equal numbers of men and women. 2. Individual has a self-reported BMI of 18.5 to 39.9 kg/m2, inclusive. 3. Individual has been taking tirzepatide (≥10 mg weekly injection), semaglutide (≥2.0 mg weekly injection), or liraglutide (≥2.4 mg daily injection) for at least 4 weeks and plans to continue to take it throughout the duration of the study. 4. Individual has attained a high school diploma or a General Educational Development (GED) equivalent. 5. Individual has not participated in another research study within 30 days of the screening visit. 6. Individual is willing and able to undergo the scheduled study procedures. 7. Individual understands the study procedures and signs forms documenting informed consent to participate in the study and authorization for release of relevant protected health information to the study Investigator. Exclusion Criteria: 1. Individual has a clinically significant medical condition that, in the opinion of the Investigator, could interfere with the interpretation of the study results. Health conditions may include history or presence of clinically important GI, cardiac, renal, hepatic, endocrine, pulmonary, biliary, pancreatic, or neurological disorders that may affect the participant's ability to adhere to the study protocol and/or affect study outcomes, in the judgment of the Investigator. Clinically important GI conditions included but are not limited to: inflammatory bowel disease, irritable bowel syndrome, gastroparesis, clinically important lactose intolerance. 2. Individual habitually consumes \>8 g fiber per 1000 kcal per day. 3. Individual had a recent (within two weeks of screening) episode of acute GI illness such as nausea, vomiting, or diarrhea. 4. Individual has a history of frequent diarrhea or constipation prior to beginning GLP-1 receptor agonist that, in the opinion of the Investigator, could interfere with the interpretation of the study results. 5. Individual has a history of stomach or GI surgery (e.g., gastric bypass, cholecystectomy) that in the opinion of the Investigator, could interfere with evaluation of the study outcomes. 6. Individual uses medications (over-the counter or prescription) or dietary supplements known to influence gastrointestinal motility including laxatives, enemas, or suppositories; prokinetic drugs; anti-diarrheal agents, anti-spasmotics; fiber supplements; and prebiotic and probiotic supplements (Appendix 6). A 14-day washout phase prior to day 1 is allowed for participants taking any of these products. 7. Daily use of non-steroidal anti-inflammatory drugs (NSAIDs). 8. Individual has a history of cancer in the prior 2 years, except non-melanoma skin cancer or carcinoma in situ of the cervix. 9. Individual has a history of a diagnosed eating disorder (e.g., anorexia or bulimia nervosa). 10. History of any major trauma or major surgical event within 2 months of visit 1. 11. Use of tobacco/nicotine products (e.g., cigarette smoking, vaping, chewing tobacco) within 12 months of visit 1. 12. Use of hemp/marijuana products within 12 months of visit 1. Occasional use (e.g., once or twice a month) within 12 months of visit 1 is allowed but requires at least a 14-day washout prior to day 1 and the participant must be willing to refrain from use during the study. 13. Individual is a female who is pregnant, planning to be pregnant during the study period, lactating, or is of childbearing potential and is unwilling to commit to the use of a medically approved form of contraception throughout the study period. 14. Individual has an allergy, sensitivity, or intolerance to any foods. 15. Individual has extreme dietary habits (e.g., vegan, Atkins diet, etc.). 16. Individual has signs or symptoms of an active infection of clinical significance or has taken antibiotics within 10 days prior to any visit (washout is permitted for re-scheduling of a visit). 17. Individual has a current or recent history (past 12 months of screening) or strong potential for illicit drug or excessive alcohol intake defined as \>14 drinks per week (1 drink = 12 oz beer, 5 oz wine, or 1.5 oz hard liquor). 18. Individual has been exposed to any non-registered drug product within 30 days prior to screening. 19. Individual has a condition the Investigator believes would interfere with his or her ability to provide informed consent, comply with the study protocol, or which might confound the interpretation of the study results or put the person at undue risk.


Study Plan

Find out more about all the medication administered in this study, their detailed description and what they involve.
Treatment Groups
Study Objectives
4 intervention groups 

are designated in this study

25% chance 

of being blinded to the placebo group

Treatment Groups
Group I
Experimental

Bar with Inulin - high fiber
Group II
Experimental

Bar with a fiber blend of psyllium husk and bran fibers - high fiber
Group III
Experimental

Bar with Resistant Starch type 4 - High Fiber
Group IV
Placebo

Snack Bar - Low Fiber
Study Objectives
Primary Objectives

Composite GI Symptom Score is from the GI Tolerability Questionnaire. The composite score will be calculated as the sum of the individual components (nausea, abdominal pain, bloating, intestinal rumbling, and flatulence). The ratings will be coded as: 1 = none/much less than usual, 2 = less than usual, 3 = about usual, 4 = more than usual, and 5 = much more than usual. There will be one composite score per day. Baseline will be defined as the average of the composite scores for the 3-day baseline period. The value for each intervention will be defined as the average of the composite scores for the 7-day intervention period.
Secondary Objectives

For each individual component, the ratings for the 3-day baseline period and the 7-day intervention period will be summed and divided by 3 and 7, respectively, before the change from baseline is calculated.

The scores for the 3-day baseline period and the 7-day intervention period will be summed and divided by the number of bowel movements that occurred during the respective period before the change from baseline is calculated.

The raitings for the 3-day baseline period and the 7-day intervention period will be summed and divided by the number of bowel movements that occurred during the respective period before the change from baseline is calculated.

Study Centers

These are the hospitals, clinics, or research facilities where the trial is being conducted. You can find the location closest to you and its status.
This study has 2 locations
Recruiting
Excellence Medical and ResearchMiami Gardens, United StatesSee the location
Recruiting
Health AwarenessPort St Lucie, United States

Recruiting
2 Study Centers
;