Actively Recruiting
Prebiotic Effects of California Grapes on Gut Health and Cardiometabolic Health in Overweight Men and Women
Led by University of California, Davis · Updated on 2026-04-13
40
Participants Needed
1
Research Sites
86 weeks
Total Duration
On this page
Sponsors
U
University of California, Davis
Lead Sponsor
C
California Table Grape Commission
Collaborating Sponsor
AI-Summary
What this Trial Is About
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
CONDITIONS
Official Title
Prebiotic Effects of California Grapes on Gut Health and Cardiometabolic Health in Overweight Men and Women
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Post-menopausal women (no menstruation for at least two years)
- Overweight or obese with BMI between 25 and 35 kg/m2
- Stable treatment for type 2 diabetes or metabolic syndrome
- Ability to understand the study and provide written consent
- Willingness to accept randomization, undergo testing and interventions, and provide stool and blood samples
You will not qualify if you...
- Started menopausal hormone replacement therapy less than 6 months ago
- Taken antibiotics or prebiotics within the last 3 months
- On antidiabetic treatment involving insulin (for type 1 diabetes)
- Vegetarian or vegan and unable to follow the modified diet
- Serious medical conditions such as coronary artery disease, uncontrolled hypertension, stroke, heart failure, insulin-dependent diabetes, liver disease, active cancer, or anemia
- Psychiatric diseases interfering with understanding or participation
- History of eating disorders in the last 5 years
- History of substance or alcohol abuse
- Participated in weight loss programs, used anti-obesity medication, or had bariatric surgery within last 3 months
- Current smoker or smoked within last 180 days
- Used dietary supplements containing polyphenols in the past month
- Engages in strenuous exercise over 10 hours per week
AI-Screening
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Trial Site Locations
Total: 1 location
1
Ragle Human Nutrition Center
Davis, California, United States, 95616
Actively Recruiting
Research Team
D
Dragan Milenkovic, PhD
CONTACT
S
Shannon H Trinh, MS, RD
CONTACT
How is the study designed?
Study Type
INTERVENTIONAL
Masking
QUADRUPLE
Allocation
RANDOMIZED
Model
CROSSOVER
Primary Purpose
PREVENTION
Number of Arms
2
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