Effect of Watermelon on Cardiometabolic Health

Launched by UNIVERSITY OF CALIFORNIA, LOS ANGELES · May 28, 2025

Keywords

ClinConnect Summary

This clinical trial is investigating the effects of drinking 355 ml of watermelon juice on heart health and overall metabolic health. Researchers want to find out if this juice can help improve important health markers, such as blood pressure, heart rate, and cholesterol levels. They are also looking at how well the body can protect itself from damage caused by harmful substances when the skin is exposed to sunlight. Participants will be assessed right after drinking the juice and again after consuming it daily for four weeks to see both immediate and longer-term effects.

To be eligible for this study, you must be a generally healthy postmenopausal woman between the ages of 25 and 40 with a specific body weight range and mild high blood pressure. You should be willing to stick to your normal diet and exercise routine, and avoid any skin products during the study. It’s important that you do not have any serious health issues, allergies to watermelon, or other specific conditions that would prevent you from participating. If you join, you can expect to attend two visits—one for testing before the juice consumption begins and another after four weeks of daily intake.

Gender

FEMALE

Eligibility criteria

• Inclusion Criteria:
• • Female
• • Generally healthy
• • Postmenopausal
• • BMI 25-40 kg/m2
• • Systolic blood pressure 120-139 mmHg and/or diastolic 80-89 mmHg
• • Fitzpatrick Skin type II-IV
• • Consume a typical Western diet (low in polyphenol/lycopene-rich foods and fiber)
• • Willing to maintain habitual dietary and exercise patterns for the study duration
• • Willing to maintain normal skin care products and pattern for the duration of the study
• • Willing to come to Baseline Visit B and Week 4 study visits without any makeup and skin products on
• • Subjects must read and sign the Institutional Review Board-approved written informed consent prior to the initiation of any study specific procedures or enrollment. A subject will be excluded for any condition that might compromise the ability to give truly informed consent.
• Exclusion Criteria:
• • Non-English speaker
• • Vegetarian/vegan
• • Known watermelon allergy
• • Skin-related prescription medication, supplements, or non-prescription cosmeceutical agents
• • Initiation of topical or oral prescription steroids and/or anti-inflammatory medications within 30 days prior to study enrollment
• • Excessive exposure to either natural or artificial sunlight. Exposure to sunlight will be evaluated using Fitzpatrick Skin Type test score. Individuals receiving scores higher than the upper cutoff of the proposed range for the specific skin type will be excluded
• • Screening laboratory values outside of the normal range that is considered clinically significant for study participation by the investigator
• • Documented chronic disease, including diabetes, renal or liver diseases, metabolic syndrome, active cancer, MI or stroke, history of gastric bypass or GI disease (e.g., Crohn's disease, IBD, diverticulosis, diverticulitis, etc.)
• • Taking medications or supplements known to affect metabolism or gut microbiota composition (antibiotics within the past 3 months, probiotics, fiber, etc.), unless willing to stop for the study duration
• • Taking exogenous hormones (e.g., hormone replacement therapy)
• • Recent weight fluctuations (\>10% in the last 6 months)
• • Smoker or living with a smoker
• • Use of \>20 g of alcohol per day
• • Unable or unwilling to comply with the study protocol (including unwillingness to avoid watermelon and other lycopene-rich foods for the whole duration of the study)
• • Unable to provide consent