Identifying biomarkers linked to fruit and vegetable consumption

University of California (UC), Davis Dietary Biomarkers Development Center

This study is testing whether certain markers in blood and urine can show how much fruits and vegetables people eat, to help improve how we understand nutrition.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 280 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: University of California, Davis (Academic / other)
• Drugs / interventions: chemotherapy, radiation
• Locations: 1 site (Davis, California)
• Trial ID: NCT05621863 on ClinicalTrials.gov

What this trial studies

This research aims to discover specific biomarkers in blood and urine that correlate with the intake of various fruits and vegetables. The study employs a randomized crossover dietary intervention to assess how metabolites respond to different dietary exposures. It also includes a controlled diet intervention to validate these biomarkers as predictors of fruit and vegetable consumption. Ultimately, the goal is to establish an objective method for evaluating nutritional status in both community and clinical settings, addressing limitations of traditional dietary reporting methods.

Who should consider this trial

Good fit: Ideal candidates are adults with a BMI between 18.5 and 39.9 who are willing to participate in dietary interventions and provide biological samples.

Not a fit: Patients with gastrointestinal disorders, recent hospital admissions for serious conditions, or those undergoing active cancer treatment may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide a reliable way to assess dietary intake, improving nutritional guidance and health outcomes for individuals.

How similar studies have performed: While the approach of identifying dietary biomarkers is established, this specific study's methodology and focus on fruit and vegetable intake may offer novel insights.

Eligibility criteria

Inclusion Criteria:

* Body Mass Index (BMI) 18.5-39.9 kg/m\^2
* Willingness to provide urine and have blood drawn

Exclusion Criteria:

* Pregnancy or lactation
* Allergy or aversion to foods provided in test diet
* History of gastrointestinal disorders including the following:

  1. Ulcerative colitis or Crohn's disease
  2. Celiac sprue
  3. Hereditary non-polyposis colorectal cancer (HNPCC)
  4. Familial adenomatous polyposis
  5. Pancreatic disease
  6. Liver disease
* Previous gastrointestinal resection or bariatric surgery
* Bleeding disorders that preclude blood draws
* Recent hospital admissions (past 6 months) for myocardial infarction (MI), cerebrovascular accident (CVA), or congestive heart failure (CHF)
* Cardiovascular disease (CVD) under physician guided therapy that is not medically stable
* Cancer under radiation or chemotherapy treatment that is active or within 6 months of treatment
* Weight change (± 5% in the last 3 months)
* Regular alcohol intake of \> 2 drinks/day (equivalent to 720 mL of beer, 240 mL of wine, or 90 mL of spirits), and unwilling to abstain during feeding periods
* Use of tobacco and/or marijuana, hookahs, e-cigarettes, or vapes and not willing to abstain during feeding periods
* Use of illicit drugs and not willing to abstain during feeding periods
* BMI \>40 kg/m\^2
* Regular (daily to weekly) use of over-the-counter (OTC) weight-loss aids and unwilling or unable to stop taking these during feeding periods
* Regular (daily to weekly) use of OTC anti-inflammatories and unwilling or unable to stop taking these during feeding periods
* Unwilling to stop taking OTC dietary supplements that interfere with the test foods being studied including pills, chewables, liquids or powders for the following (may continue if vitamin supplement is prescribed by a medical doctor):

  1. Protein supplements
  2. Soy
  3. Fiber
  4. Flaxseed
  5. Fish oil (including cod liver oil)
  6. Probiotics
  7. Carotenoids
  8. Selenium
  9. Other antioxidants
  10. Other phytochemicals
  11. Glucosamine
  12. Chondroitin
* Oral or IV antibiotic use in the past 6 months (could defer participation until 6 months post-completion of course of antibiotics)
* Seated blood pressure \>140/90 mmHg
* Fasting clinical lab values outside of the following ranges:

  1. Fasting Glucose: 54-125 mg/dL
  2. Urea: 6-50 mg/dL
  3. Creatinine: 0.4-1.3 mg/dL
  4. Estimated Glomerular Filtration Rate (eGFR): \>60 mL/min
  5. Sodium: 133-146 mmol/L
  6. Alanine Transaminase (ALT): 5-60 U/L
  7. Aspartate Aminotransferase (AST): 5-40 U/L
  8. Alkaline Phosphatase (ALP): 20-135 U/L
  9. Total Bilirubin: 0.0-1.9 mg/dL
  10. Total Protein: 5-9.0 g/dL
  11. Albumin: 3.5-5.9 d/L
  12. Low-density Lipoprotein (LDL) Cholesterol: \<160 mg/dL
  13. Triglycerides: \<500
  14. White Blood Cells: 3-10.5 Kl/µL
  15. Hematocrit: 35-48 g/dL (women), 37.5-49 g/dL (men)
* Current use of the following prescription medications:

  1. Diuretics
  2. Steroids (oral): daily oral any dose within 1 month of study (except for oral contraceptive pills)
  3. Opiates: any use within 1 month of study
  4. Hypolipidemic agents that affect GI or renal function (ie. fibrates)
  5. Hypoglycemic medications other than metformin (ie. insulin, SGLT2 inhibitor, α-glucosidase inhibitor)
  6. Psychiatric medications that affect metabolism/renal function (anti-psychotics, lithium)
  7. Biologics/immune modulators (ie. rheumatoid arthritis, psoriasis, other rheumatologic/hematologic active disease)
  8. Anti-coagulants (coumadin, heparin, Eliquis, etc.)
  9. HIV/HAART medications (dyslipidemia inducing)
* Inability to freely give informed consent

Where this trial is running

Davis, California

• USDA ARS Western Human Nutrition Research Center — Davis, California, United States (Recruiting)

Study contacts

• Principal investigator: Carolyn M Slupsky, PhD — University of California, Davis
• Study coordinator: Ellen L Bonnel, PhD

Conditions Biomarkers; Metabolomics; Diet; Fruit; Vegetables; Biomarker; Urine; Blood