Obesity and OverweightNCT06588218
Effect of Watermelon on Gut and Cardiometabolic Health
A study testing Watermelon and Belvita Breakfast Sandwich + 12 oz Water in people with Obesity and Overweight and Dysbiosis, run by Florida State University at 1 site in United States.
Trial summary
The goal of this clinical trial is to evaluate the effect of daily fresh watermelon consumption for 6-weeks on gut health, including microbiome diversity, gut barrier and immune function in young adults with overweight and obesity. The main questions it aims to answer are: 1. Read more about this study
- Who is it for?
- Ages 18 to 30 years
- Conditions the study is for
- Obesity and Overweight, Dysbiosis
- What is being tested?
- Watermelon and Belvita Breakfast Sandwich + 12 oz Water
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 36 participants
- Where
- 1 siteUnited States
- Study dates
- 13 Oct 2024to Dec 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 30 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Between 18 and 30 years old
- Ability to speak and read in English
- Overweight or Obese Class 1 and 2 (BMI ≥ 25 - 39.9 kg/m2)
Who cannot join
- Intake of antibiotics in the last 3 months
- Intake of pre/pro/postbiotics in the last 3 months
- Current or past (within the last 6 months) user of tobacco, marijuana, or E-cigarette products
- Cardiovascular disease (will not exclude for hypertension), gastrointestinal disease (ulcerative colitis, celiac, Crohn's disease, diverticulosis, peptic ulcers, small intestinal bacterial overgrowth, short bowel syndrome), neurological (multiple sclerosis, meningitis, recent stroke) or endocrine disorders (uncontrolled thyroid disorders, growth hormone disorders, adrenal gland disorders, uncontrolled diabetes - A1C greater than 9%).
- Food allergy to study foods
- Any allergy to melon
Show all 12Show fewer
- Any allergy to the isocaloric snack (gluten)
- Regular consumption of watermelon greater than 2 servings / week
- Current heavy alcohol use (≥ 15 drinks / week for men, ≥ 8 drinks / week for women
- Class 3 Obesity (BMI \> 40 kg/m2)
- Current user of Citrulline, Arginine, Nitric Oxide or other supplements known to affect nitric oxide synthesis (beet root juice or any beet supplement, Pycnogenol / Pine bark extract)
- Known to be currently pregnant (self-disclosed)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Cole Patoine, M.S contact
United States1 site, 1 recruiting
- Recruiting
Florida State University - Gut Biome Lab
Tallahassee, Florida, 32306
Jania Kadar, +1-850-644-1828, thegutbiomelab@fsu.edu
Ravinder Nagpal, PhD
About this study
Official title: Effect of Daily Fresh Watermelon Consumption on Gut and Cardiometabolic Health in Young Adults With Overweight and Obesity
The goal of this clinical trial is to evaluate the effect of daily fresh watermelon consumption for 6-weeks on gut health, including microbiome diversity, gut barrier and immune function in young adults with overweight and obesity. The main questions it aims to answer are:
- Will consuming fresh watermelon daily for 6-weeks will improve intestinal barrier health and increase microbiome diversity such as an increased population of beneficial 'probiotic' bacteria when compared to control participants consuming a low-fat snack?
- Will consuming fresh watermelon daily for six-weeks will improve other health measures, including body-composition, blood pressure, blood vessel function, blood lipid profiles, and measures of inflammation, as compared to control participants consuming a low-fat snack for the same time period?
- Conditions
- Obesity and Overweight, Dysbiosis
- Being tested
- Watermelon, Belvita Breakfast Sandwich + 12 oz Water
- Keywords
- Gut Microbiome, Dysbiosis, Diet, Overweight, Obesity, Watermelon, Lycopene, Citrulline, Metagenomic, vascular
- Medical subject headings
- Obesity, Overweight, Dysbiosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
WatermelonOther
Also called Whole Watermelon, Diced Watermelon
2.5 cups of whole fresh watermelon (~375 grams, 115 kcals, 0.5g fat, 1.5g fiber, 17,225mcg lycopene, 30.75mg vitamin C) of fresh watermelon daily for six weeks
Belvita Breakfast Sandwich + 12 oz WaterOther
Also called Isocaloric Snack, Breakfast Sandwich, Control Snack
Belvita breakfast sandwich; 115 kcals, 1.5g fiber, 4.5g fat, 0mg lycopene, 0mg vitamin C) as well as 12 ounces of water
| Study group | Role | What they receive |
|---|---|---|
| Watermelon Condition | Experimental | This group will maintain a normal diet supplemented with 2.5 cups (~375 grams, 115 kcals, 0.5g fat, 1.5g fiber, 17,225mcg lycopene, 30.75mg vitamin C) of fresh watermelon daily for six weeks Receives: Other: Watermelon |
| Control Condition | Active comparator | This group will maintain a normal diet supplemented with an isocaloric control snack (Belvita breakfast sandwich; 115 kcals, 1.5g fiber, 4.5g fat, 0mg lycopene, 0mg vitamin C) as well as 12 ounces of water Receives: Other: Belvita Breakfast Sandwich + 12 oz Water |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Gut Microbiome Diversity
Collected fecal samples will be used to determine microbiome profiles, including diversity and composition of bacteria.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Oral Microbiome Diversity
Oral swab samples are collected to determine oral diversity and composition of bacteria in the mouth before and after intervention.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Secondary outcomes (14)
Change in Gut Transit Time
Evaluate changes in gut transit time after watermelon or control snack consumption from baseline to final analysis, using a blue-dye capsule.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Arterial Stiffness
Evaluate the effects of watermelon on arterial stiffness, determined by measuring Pulse Wave Analysis (PWA) and Pulse Wave Velocity (PWV). These are captured by the SphygmoCor XCEL System through the descending aorta to the femoral artery. The aortic pulse wave velocity is detected from carotid and femoral arterial pulses measured non-invasively and simultaneously
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Endothelial Function
Evaluate the effects of watermelon on macrovascular endothelial function, which will be evaluated using the flow-mediated dilation (FMD) technique using a Finapres device, which measures the arterial dilation response following acute occlusion of the brachial artery.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Ambulatory Blood Pressure
Evaluate the effect of watermelon on ambulatory blood pressure (systolic and diastolic), determined using a 12-hour ambulatory blood pressure monitor (TM-2440). The 12-hour ambulatory blood pressure monitor will collect blood pressure readings every 20 minutes during waking hours only.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Waist and Hip Circumference
Evaluate changes in waist and hip circumference (centimeters), as well as waist-hip ratio at each study visit before, after and during watermelon consumption.
Measured: Screening, Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Body Composition
Evaluate changes in body composition, including lean mass (kg), fat mass kg), and total body water (kg). This is assessed using a bioimpedance spectroscopy device (ImpediMed SBF7) at each study visit before, after and during watermelon consumption.
Measured: Screening, Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Habitual Dietary Intake
Assess changes in habitual dietary intake via 3-day food logs, analyzed using nutrient analysis software.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Biomarkers of Inflammation
Relevant biomarkers are to be collected via venous blood samples to determine changes in inflammation, including but not limited to C-reactive protein (CRP), IL-1 (Interleukin-1), IL-1 beta, IL-6, IL-10, IL-17, IL-23, Tumor Necrosis Factor Alpha (TNF-a), Interferon-gamma (IFN-Y). All will be expressed in units of pg/mL.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Biomarkers of Appetite
Relevant biomarkers are to be collected via venous blood samples to determine changes in appetite including Insulin, Glucagon, glucagon-like peptide 1 (GLP-1), Adiponectin, Leptin, Ghrelin, and Peptide YY. All will be expressed in units of pg/mL.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Biomarkers of Intestinal Barrier Function
Relevant biomarkers are to be collected via venous blood samples to determine changes in intestinal barrier function including LPS (lipopolysaccharides), LBP (lipopolysaccharide binding protein), CD14, Secretory IgA. All will be expressed in units of pg/mL.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Biomarkers of Cardiometabolic Health
Relevant biomarkers are to be collected via venous blood samples to determine changes in cardiometabolic health including HDL, LDL, total cholesterol, and triglycerides. All will be expressed in units of mg/dL.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Recent Dietary Intake
Assess changes in dietary intake via 24 hr recalls, analyzed using nutrient analysis software.
Measured: Screening, Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Body Weight
Evaluate changes in body weight (kg) at each study visit before, after and during watermelon consumption.
Measured: Screening, Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Body Mass Index
Evaluate changes in Body Mass Index (kg/m2) before, during and after consumption of watermelon.
Measured: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 Sep 2024
- Study start13 Oct 2024
- Primary completionDec 2026 (estimated)
- Study completionDec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Obesity and OverweightStudies of the same condition, open and under way.
- More trials run by Florida State UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Enrolment
- 36 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Florida State University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Ravi Nagpal, Florida State University
- Investigators
- Ravinder Nagpal, PhD, Principal investigator, Florida State University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06588218
- Sponsor's protocol ID
- STUDY00005203
- Status last verified
- Apr 2026
- First submitted
- 3 Sep 2024
- Last updated
- 9 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Deidentified IPD will not be retain past three years, at the time of this submission the researchers does not plan to make IPD available
Study at a glance
From the registry record, last updated by the sponsor on 9 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effect of Daily Fresh Watermelon Consumption on Gut and Cardiometabolic Health in Young Adults With Overweight and Obesity
- ClinicalTrials.gov ID
- NCT06588218
- Acronym / sponsor ID
- STUDY00005203
- Conditions
- Obesity and Overweight, Dysbiosis
- Keywords
- Gut Microbiome, Dysbiosis, Diet, Overweight, Obesity, Watermelon, Lycopene, Citrulline
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 36 participants (estimated)
- Lead sponsor
- Florida State UniversityUniversity, hospital or other
- Study start
- 13 Oct 2024 (actual)
- Primary completion
- Dec 2026 (estimated)
- Study completion
- Dec 2026 (estimated)
- First posted
- 19 Sep 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this clinical trial is to evaluate the effect of daily fresh watermelon consumption for 6-weeks on gut health, including microbiome diversity, gut barrier and immune function in young adults with overweight and obesity. The main questions it aims to answer are:
- Will consuming fresh watermelon daily for 6-weeks will improve intestinal barrier health and increase microbiome diversity such as an increased population of beneficial 'probiotic' bacteria when compared to control participants consuming a low-fat snack?
- Will consuming fresh watermelon daily for six-weeks will improve other health measures, including body-composition, blood pressure, blood vessel function, blood lipid profiles, and measures of inflammation, as compared to control participants consuming a low-fat snack for the same time period?
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Watermelon Condition | Experimental | Other: WatermelonThis group will maintain a normal diet supplemented with 2.5 cups (~375 grams, 115 kcals, 0.5g fat, 1.5g fiber, 17,225mcg lycopene, 30.75mg vitamin C) of fresh watermelon daily for six weeks |
| Control Condition | Active comparator | Other: Belvita Breakfast Sandwich + 12 oz WaterThis group will maintain a normal diet supplemented with an isocaloric control snack (Belvita breakfast sandwich; 115 kcals, 1.5g fiber, 4.5g fat, 0mg lycopene, 0mg vitamin C) as well as 12 ounces of water |
Who may qualify
- Ages
- 18 to 30 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- Between 18 and 30 years old
- Ability to speak and read in English
- Overweight or Obese Class 1 and 2 (BMI ≥ 25 - 39.9 kg/m2)
Key exclusion criteria (12 listed)
- Intake of antibiotics in the last 3 months
- Intake of pre/pro/postbiotics in the last 3 months
- Current or past (within the last 6 months) user of tobacco, marijuana, or E-cigarette products
- Cardiovascular disease (will not exclude for hypertension), gastrointestinal disease (ulcerative colitis, celiac, Crohn's disease, diverticulosis, peptic ulcers, small intestinal bacterial overgrowth, short bowel syndrome), neurological (multiple sclerosis, meningitis, recent stroke) or endocrine disorders (uncontrolled thyroid disorders, growth hormone disorders, adrenal gland disorders, uncontrolled diabetes - A1C greater than 9%).
- Food allergy to study foods
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| WatermelonAlso: Whole Watermelon, Diced Watermelon2.5 cups of whole fresh watermelon (~375 grams, 115 kcals, 0.5g fat, 1.5g fiber, 17,225mcg lycopene, 30.75mg vitamin C) of fresh watermelon daily for six weeks | Other | Watermelon Condition |
| Belvita Breakfast Sandwich + 12 oz WaterAlso: Isocaloric Snack, Breakfast Sandwich, Control SnackBelvita breakfast sandwich; 115 kcals, 1.5g fiber, 4.5g fat, 0mg lycopene, 0mg vitamin C) as well as 12 ounces of water | Other | Control Condition |
Primary outcome
Change in Gut Microbiome Diversity
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Collected fecal samples will be used to determine microbiome profiles, including diversity and composition of bacteria.
Change in Oral Microbiome Diversity
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Oral swab samples are collected to determine oral diversity and composition of bacteria in the mouth before and after intervention.
14 secondary outcomes
Change in Gut Transit Time
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Arterial Stiffness
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Endothelial Function
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Ambulatory Blood Pressure
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Waist and Hip Circumference
Time frame: Screening, Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Body Composition
Time frame: Screening, Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Habitual Dietary Intake
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Biomarkers of Inflammation
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Biomarkers of Appetite
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Biomarkers of Intestinal Barrier Function
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Biomarkers of Cardiometabolic Health
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Recent Dietary Intake
Time frame: Screening, Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Body Weight
Time frame: Screening, Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Change in Body Mass Index
Time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Apr 2026.
- Individual participant dataSharing planned: No. Deidentified IPD will not be retain past three years, at the time of this submission the researchers does not plan to make IPD available
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Cole Patoine, M.S contact
Ravinder Nagpal, PhD principal investigator
Florida State University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Watermelon and Belvita Breakfast Sandwich + 12 oz Water in people with Obesity and Overweight and Dysbiosis, run by Florida State University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 9 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Ravinder Nagpal, PhD (850-644-1829, rnagpal@fsu.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in Gut Microbiome Diversity (time frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16).). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Apr 2026.