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Browse medicines, supplements, herbs, and health foods. Each profile brings community reports and linked research into one clear view.
Browse medicines, supplements, herbs, and health foods. Each profile brings community reports and linked research into one clear view.
Amino acid named after watermelon (Citrullus) that the kidneys turn into arginine, so it raises blood arginine and nitric-oxide markers. Sold in two forms that are not interchangeable: pure L-citrulline, and citrulline malate, which is citrulline bound to malic acid, so a gram of it contains less citrulline. Most gym trials used citrulline malate: a meta-analysis of 8 studies found about 6% more repetitions before failure, while cycling and endurance trials were mostly negative. Blood-pressure findings are mixed: a 2018 meta-analysis found no effect, while small trials of pure L-citrulline in older, hypertensive or diabetic adults report lower aortic pressure and better artery function.
17 of 22 results reported a benefit, from 4 published studies.
4 studies, including a review of trials
These are the figures the studies reported, not a prediction for any one person. Where several studies measured the same thing in the same unit, we show a simple average and say so. Every individual result is listed below.
See every resultCardiovascular health — blood pressure, cholesterol, heart function, and circulation.
Also known as: Citrulline, Citrulline malate, L-Citrulline DL-malate
Every published result for this pair, extracted and audited.
These charts group published studies by what they reported and how they were run — green marks studies that reported a benefit for this pairing. Tiers run from pooled analyses of many trials (strongest) to one-off observational reports.
Direction of reported outcomes for L-Citrulline in heart health.
Study designs behind these findings.
Hand-selected PubMed studies, linked to the originals.
Ordered by strength of evidence, then result direction.
01Taurine supplementation as a therapeutic strategy for cellular senescence and chronic inflammation in long COVID: a systematic review and meta-analysisWang K, et al. · BMC infectious diseases · 2026PMID 41803812 ↗02Energy Drinks as the Legal Cocaine? A Comparative Review of Cardiac Physiopathological and Histopathological PatternsGhamlouch A, et al. · Cardiovascular toxicology · 2025PMID 41266869 ↗03Evaluating the efficacy of ubiquinol in heart failure patients: a systematic review and meta-analysisQazi SU, et al. · Future cardiology · 2024PMID 39049769 ↗04Insights into the cardiovascular benefits of taurine: a systematic review and meta-analysisTzang CC, et al. · Nutrition journal · 2024PMID 39148075 ↗Be the first to share what you noticed with L-Citrulline for heart health. Why counts start empty.
Every measured outcome, one row per finding - numbers exactly as reported.
| Study | Design | n | Duration | Outcome measured | Reported result | Direction |
|---|---|---|---|---|---|---|
| PMID 30284051 2018 | Meta-analysis | - | - | aortic diastolic blood pressure change | 0.26 mmHg (95% CI - 2.27, 2.80 mmHg) | No benefit |
| PMID 30284051 2018 | Meta-analysis | - | - | aortic systolic blood pressure change | 0.22 mmHg (95% CI - 4.81, 4.38 mmHg) | No benefit |
| PMID 30284051 2018 | Meta-analysis | - | - | brachial diastolic blood pressure change | - 1.56 mmHg (95% CI - 4.32, 1.20 mmHg) | No benefit |
| PMID 30284051 2018 | Meta-analysis | - | - | brachial systolic blood pressure change | 0.28 mmHg (95% CI - 2.87, 2.31 mmHg) | No benefit |
| PMID 41374029 2025 | Randomised trial | 16 | 4 weeks | aortic systolic blood pressure, during acute hyperglycaemia | reported qualitatively (p < 0.05) | Benefit |
| PMID 41374029 2025 | Randomised trial | 16 | 4 weeks | aortic systolic blood pressure, fasted state | reported qualitatively (p < 0.05) | Benefit |
| PMID 41374029 2025 | Randomised trial | 16 | 4 weeks | blood glucose concentration, during acute hyperglycaemia | reported qualitatively (p < 0.05) | Benefit |
| PMID 41374029 2025 | Randomised trial | 16 | 4 weeks | blood glucose concentration, fasted state | reported qualitatively (p < 0.05) | Benefit |
| PMID 41374029 2025 | Randomised trial | 16 | 4 weeks | brachial artery flow-mediated dilation (FMD), during acute hyperglycaemia | reported qualitatively (p < 0.05) | Benefit |
| PMID 41374029 2025 | Randomised trial | 16 | 4 weeks | brachial artery flow-mediated dilation (FMD), fasted state | reported qualitatively (p < 0.05) | Benefit |
| PMID 41374029 2025 | Randomised trial | 16 | 4 weeks | femoral-ankle pulse wave velocity (PWV), during acute hyperglycaemia | reported qualitatively (p < 0.05) | Benefit |
| PMID 41374029 2025 | Randomised trial | 16 | 4 weeks | femoral-ankle pulse wave velocity (PWV), fasted state | reported qualitatively (p < 0.05) | Benefit |
| PMID 38931289 2024 | Randomised trial | 22 | 4 weeks | aortic systolic blood pressure (change with placebo vs L-citrulline) | Δ3 ± 5 vs. Δ-4 ± 6 mmHg (p < 0.05) | Benefit |
| PMID 38931289 2024 | Randomised trial | 22 | 4 weeks | deoxygenated hemoglobin (HHb) (change with placebo vs L-citrulline) | Δ1.03 ± 0.69 vs. Δ-2.76 ± 0.77 μM (p < 0.05) | Benefit |
| PMID 38931289 2024 | Randomised trial | 22 | 4 weeks | exercise blood flow (BF) (change with placebo vs L-citrulline) | Δ17 ± 12 vs. Δ48 ± 16 mL/min (p < 0.05) | Benefit |
| PMID 38931289 2024 | Randomised trial | 22 | 4 weeks | flow-mediated dilation (FMD) (change with placebo vs L-citrulline) | Δ-0.7 ± 0.6% vs. Δ1.6 ± 0.7% (p < 0.05) | Benefit |
| PMID 38931289 2024 | Randomised trial | 22 | 4 weeks | muscle tissue oxygenation saturation index (TSI) (change with placebo vs L-citrulline) | Δ-0.84 ± 0.58% vs. Δ1.61 ± 0.46% (p < 0.05) | Benefit |
| PMID 38931289 2024 | Randomised trial | 22 | 4 weeks | vascular conductance (VC) (change with placebo vs L-citrulline) | Δ-21 ± 9 vs. Δ41 ± 14 mL/mmHg/min (p < 0.05) | Benefit |
| PMID 19851298 2010 | Randomised trial | 17 | 4 weeks | Aortic pulse pressure during cold pressor test | -3 +/- 6 mm Hg | Benefit |
| PMID 19851298 2010 | Randomised trial | 17 | 4 weeks | Aortic systolic blood pressure during cold pressor test | -4 +/- 10 mm Hg | Benefit |
| PMID 19851298 2010 | Randomised trial | 17 | 4 weeks | Blood pressure at rest | reported qualitatively | No benefit |
| PMID 19851298 2010 | Randomised trial | 17 | 4 weeks | Brachial systolic blood pressure during cold pressor test | -6 +/- 11 mm Hg | Benefit |