Prebiotic Effects of California Grapes on Gut Health and Cardiometabolic Health in Overweight Men… (NCT06544954) | Clinical Trial Compass
RecruitingNot Applicable
Prebiotic Effects of California Grapes on Gut Health and Cardiometabolic Health in Overweight Men and Women
United States40 participantsStarted 2025-05-07
Plain-language summary
The goal of this clinical trial is to assess the impact of table grape consumption on gut microbiome, intestinal permeability, systemic inflammation, and vascular function in healthy overweight men and women aged 45-70 years. The main questions it aims to answer are:
* Does daily grape intake alter intestinal microbiome composition and intestinal permeability?
* Are changes in gut microbiota and intestinal permeability correlated with changes in cardiometabolic risk factors (inflammation, vascular function, lipid profiles)?
* Does response to grape intake on gut microbiota, intestinal permeability, cardiometabolic and inflammatory markers differ between men and women?
* Are metabolic pathways modified by grape consumption able to explain the link between gut health and cardiometabolic factors?
Researchers will compare freeze-dried grape powder to placebo powder to see if grape powder improves cardiometabolic risk factors.
Participants will
* Consume the powder dissolved in water twice daily for 3 weeks
* Follow their usual diet, modified to limit polyphenol-rich foods
* Visit the clinic at the beginning and end of the intervention for vascular measurements and blood sample collection
* Complete a 3-day 24-hour dietary recall and collect stool sample before each visit
Who can participate
Age range
45 Years – 70 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* post-menopausal women (cessation of menstruation for minimum two years)
* overweight and obese (BMI between 25-35 kg/m2)
* stable treatment for type 2 diabetes or metabolic syndrome
* ability to understand the intervention concept and written consent to participate
* willingness to accept randomization, undergo testing and intervention procedures, and deliver stool and blood samples
Exclusion Criteria:
* menopausal hormone replacement therapy started within less than 6 months
* antibiotics, prebiotics within last 3 months
* antidiabetic treatment involving insulin (for type 1 diabetes)
* vegetarian/vegan and not able to follow modified diet
* any serious medical condition including but not limited to coronary artery disease, uncontrolled hypertension, stroke, congestive heart failure, insulin-dependent diabetes, liver disease, active cancer and anemia
* psychiatric disease that interferes with the understanding and implementation of the intervention
* history of eating disorders such as bulimia nervosa, anorexia nervosa, severe binge eating disorder in the last 5 years
* history of substance abuse or alcohol abuse
* involvement in a weight loss intervention program (including anti-obesity medication) within last 3 months or have had bariatric surgery
* current smokers (within last 180 days)
* use of dietary supplements containing polyphenols in the past 1 month
* strenuous exercise greater than 10 hours per week
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.