Recruiting

Watermelon

Sponsor:

Florida State University

Code:

NCT06588218

Conditions

Obesity and Overweight

Dysbiosis

Eligibility Criteria

Sex: All

Age: 18 - 30

Healthy Volunteers: Not accepted

Interventions

Watermelon

Belvita Breakfast Sandwich + 12 oz Water

Study Details

Brief 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. 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?
2. 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

Study ID

NCT06588218

Start date

Oct 13, 2024

Status verified date

Apr, 2026

Completion date

Dec, 2026

Anticipated

Primary completion date

Dec, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 30

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • 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)

Exclusion Criteria:

  • 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
  • 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)

Study Design

Enrollment

36 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: Watermelon Condition

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

active comparator: Control Condition

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

Interventions

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 Water

Belvita breakfast sandwich; 115 kcals, 1.5g fiber, 4.5g fat, 0mg lycopene, 0mg vitamin C) as well as 12 ounces of water

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). ]
  • Change in Oral Microbiome Diversity [ Time Frame: Baseline (day 0), Visit 2 (week 6), Visit 3 (week 10), Visit 4 (week 16). ]

Central Contacts and Locations

Central contacts

Ravinder Nagpal, PhD

850-644-1829rnagpal@fsu.edu

Cole Patoine, M.S

cjp23a@fsu.edu

Locations

Florida State University - Gut Biome Lab

Recruiting

Tallahassee, Florida, United States, 32306

Contacts

Jania Kadar

+1-850-644-1828thegutbiomelab@fsu.edu

Principal Investigator:

Ravinder Nagpal, PhD

More Information

Sponsor

Florida State University

Last update posted

Apr 9, 2026

Last verified

Apr, 2026

Keywords

  • Gut Microbiome
  • Dysbiosis
  • Diet
  • Overweight
  • Obesity
  • Watermelon
  • Lycopene
  • Citrulline
  • Metagenomic
  • vascular

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Florida State University on 2026-04-09.