The Study
Effect of microencapsulated watermelon (Citrullus Lanatus) rind on flow-mediated dilation and tissue oxygen saturation of young adults
This study gave 11 healthy young people a special watermelon powder and saw that their blood vessels opened up a little more for a short time. It doesn't prove the powder fixes heart problems — it just shows a quick, small change that might be related.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Scientists gave healthy young people a special powder made from watermelon rind that has a chemical called citrulline, which helps make nitric oxide — a molecule that helps blood vessels relax.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 537 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1The 1.5% improvement in blood vessel function is small and temporary — like a quick boost that fades after two hours, not a lasting change.
- 2After eating it, citrulline in the blood went up by 150%, blood vessel function improved by 1.5% at 60 minutes, and stayed normal after 2 hours.
- 3Oxygen levels in tissues didn't change.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
European Journal of Clinical Nutrition
Year
2022
Authors
Mônica Volino-Souza, Gustavo Vieira de Oliveira, C. Conte‐Junior, T. Alvares
Related Content
Claims (6)
Taking 4 grams of L-citrulline from microencapsulated watermelon rind raises plasma L-citrulline levels by about 150% within one hour in healthy young adults and also increases plasma L-arginine levels.
Taking 4 grams of L-citrulline from microencapsulated watermelon rind causes a temporary increase in blood vessel response that reaches its highest point at 60 minutes and returns to normal by 120 minutes in healthy young adults.
Consuming 30 grams of microencapsulated watermelon rind with 4 grams of L-citrulline increases blood vessel dilation by about 1.5% in healthy young adults within one hour and does not change tissue oxygen levels.
Taking 4 grams of L-citrulline from microencapsulated watermelon rind does not change tissue oxygen levels in healthy young adults over two hours after ingestion, but it does improve blood vessel function.
Microencapsulated watermelon rind raises blood levels of L-citrulline to the same extent as purified L-citrulline supplements in healthy young adults, and it briefly improves endothelial function without affecting other aspects of vascular health.
Watermelon contains more citrulline than any other food, and citrulline is converted in the body to nitric oxide.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.