NCT05545865 · University of California, Davis
Chardonnay Marc and Vascular Response
What this study is about
This study aims to obtain data on the potential influence of Vine to Bar product(s) containing Chardonnay marc on cardiometabolic health. These initial studies will inform the design and timing of data collection for future dietary intervention trials that will examine the influence of Chardonnay marc intake on outcomes/biomarkers of both cardiometabolic health and the gut microbiome.
View original scientific description
This study aims to obtain data on the potential influence of Vine to Bar product(s) containing Chardonnay marc on cardiometabolic health. These initial studies will inform the design and timing of data collection for future dietary intervention trials that will examine the influence of Chardonnay marc intake on outcomes/biomarkers of both cardiometabolic health and the gut microbiome. This includes collecting data on the potential differences in response to the products based on the unique food matrix for each of the products that will be tested. Moreover, as there is a paucity of data on the influence of cocoa flavanol intake on vascular function beyond 4 hours post intake, the response of the selected outcomes will be assessed after 6 hours of flavanol intake. This is a time point that captures the increased circulating presence of microbial derived flavanol metabolites.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Screening or Visit 1 Reactive Hyperemia Index (RHI; EndoPAT 2000) \< 2.0
- Subject is willing and able to comply with the study protocols.
- Subject is willing to participate in all study procedures
- BMI 25.0 - 35 kg/m2
Exclusion criteria
- BMI ≥ 35 kg/m2
- Indivduals that weight less than a 110 lbs
- Donation of blood within the previous 30 days
- Visit 1 Reactive Hyperemia Index (RHI; EndoPAT 2000) ≥ 2.0
- 1 ug/ml and 3 ug/ml collagen screening maximal platelet aggregatory response of \< 65%.
- Platelet counts \< 150,000 / ul
- Anemia, which includes self report, or a screening hemoglobin and hematocrit that is less than the normal reference range or as diagnosed by study physician upon review of complete blood cell count reports.
- Dislike or allergy for nuts, cocoa or grape products
- Self-reported use of daily anticoagulation agents including aspirin, NSAIDs
- Vegan, Vegetarians, food faddists or those consuming a non-traditional diet
- Fruit consumption ≥ 3 cups/day
- Vegetable consumption ≥ 4 cups/day
- Nut intake ≥ 2 servings/ week
- Coffee/tea ≥ 3 cups/day
- Dark chocolate ≥ 3 oz/day
- Self-reported restriction of physical activity due to a chronic health condition
- Self-reported chronic/routine high intensity exercise
- Self-reported diabetes
- Blood pressure ≥ 140/90 mm Hg
- Self-reported renal or liver disease
- Self-reported heart disease, which includes cardiovascular events and stroke
- Peripheral artery disease, Raynaud's syndrome
- Inability to properly place or wear the PAT probes or abnormal measurements on pre- screening PAT
- Self-reported cancer within past 5 years
- Self-reported malabsorption
- Currently taking prescription drugs or supplements.
- Supplement use or unwillingness to stop any supplement use, including herbal, plant or botanical, fish oil, oil supplements a month prior to study enrollment.
- Indications of substance or alcohol abuse within the last 3 years
- smoking, vaping, cannabis use
- Current enrollee in a clinical research study.
Where
- Davis, California
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Feb 18, 2026 · Source of record for eligibility and locations