Supplement
Beetroot, L-citrulline, and L-arginine — real short-term physiology, unproven long-term protection.
Medical Disclaimer: This content is for educational purposes only and does not constitute medical advice, diagnosis, or treatment. Information is based on current medical literature and clinical guidelines but may not apply to your specific situation. Individual responses vary based on personal medical history and concurrent conditions. Always consult qualified healthcare providers for medical decisions. Never delay seeking medical care based on content you’ve read. If experiencing a medical emergency, seek immediate medical attention.
These articles provide education to enhance your healthcare partnership. All treatment decisions should involve your healthcare team. Use this knowledge to have informed discussions, not replace medical care.
In brief: Three supplements aim to raise nitric oxide, the molecule the body uses to relax and widen blood vessels: dietary nitrate from beetroot, L-citrulline, and L-arginine. Beetroot lowers blood pressure by about 4–5 mmHg for several hours after a dose, and L-citrulline produces smaller, less consistent reductions. L-arginine’s blood pressure data are mixed, and it carries a mortality signal from the VINTAGE MI trial in patients with established cardiovascular disease. None of the three has been shown to reduce heart attacks, strokes, or cardiovascular death in a randomized trial — the biology and the short-term effects are real, but the long-term outcome evidence does not exist.
Introduction
Nitric oxide is a signaling molecule made by the endothelium, the single-cell layer that lines every blood vessel. It diffuses into the surrounding muscle and tells it to relax, which widens the vessel and improves blood flow. This is not a minor piece of physiology. It is central to how blood pressure is regulated, how coronary arteries respond when the heart demands more oxygen, and how the circulation keeps the flexibility that healthy blood flow depends on.
When nitric oxide production falls — as it does in hypertension, diabetes, and established atherosclerosis — vascular function deteriorates in ways that both precede and contribute to cardiovascular events. This impairment, called endothelial dysfunction, can be detected in population studies years before any clinical disease appears. From there, the therapeutic logic seems to follow on its own: if failing nitric oxide production underlies vascular disease, then restoring it should lower cardiovascular risk.
Three supplements pursue that logic by different biological routes. Dietary nitrate from beetroot bypasses the usual endothelial enzyme entirely. L-citrulline delivers a more usable form of that enzyme’s raw material. L-arginine supplies the raw material directly. Each acts on a different part of the same pathway, and each carries a different body of evidence.
The central question is the same for all three. The short-term blood pressure reductions are measurable and real. Whether they persist with continued use, and whether they translate into fewer cardiovascular events over years, has not been established. The biology earns these supplements a place in the evidence discussion. The outcome data — which do not yet exist — are what would earn them a place in a treatment plan.
Find Your Situation
What the evidence supports differs by clinical situation — not because one of these supplements clears a higher evidence bar than another, but because the practical considerations change. None of the three has been shown to reduce cardiovascular events in a randomized trial, so no situation below carries a proven outcome benefit. What varies is whether a modest, short-term blood pressure effect is reasonable to pursue, where caution is warranted, and which medication interactions matter. Each entry is examined in full in the sections that follow.
| Clinical profile | What the evidence shows |
| Prehypertension or stage 1 hypertension, lifestyle-first approach | Modest, short-term blood pressure reductions in randomized trials, with no long-term outcome data; eating nitrate-rich vegetables — not concentrated supplements — is the part supported by dietary guidance (1,7,9) |
| On blood pressure medication, seeking additional support | Beetroot and L-citrulline have shown small additional blood pressure reductions in some trials; the additive effect with medication is worth a prescriber’s review (1,7,8,9) |
| Healthy adult with normal blood pressure | The blood pressure effect is minimal when blood pressure is already normal; nitrate from vegetables is supported by established dietary guidance, concentrated supplements are not (1,9) |
| Established cardiovascular disease (prior heart attack, stroke, or significant ASCVD) | L-arginine carries a mortality signal from the VINTAGE MI trial in this population; any supplement here warrants cardiology review given the clinical stakes (3) |
| Considering L-arginine specifically for the heart | The blood pressure effect is real but varies widely across trials, and VINTAGE MI found a mortality signal in heart attack survivors; the evidence does not support L-arginine for cardiovascular purposes (3,4,6) |
| On nitrate medication (nitroglycerin, isosorbide), PDE5 inhibitors, or several blood pressure drugs | Combining these with nitric oxide precursors can lower blood pressure further than intended, a recognized pharmacological interaction; a prescriber’s awareness of every supplement is relevant here (10) |
How the Body Makes Nitric Oxide
The body produces nitric oxide through two separate pathways. The difference between them explains why these three supplements, despite sharing a single goal, rest on such different evidence.
The L-arginine–eNOS pathway. This is the main route. An enzyme called endothelial nitric oxide synthase — eNOS for short — sits in the cells lining the vessel wall and converts the amino acid L-arginine into nitric oxide. The enzyme is switched on by blood flow itself, including the drag of blood moving across the vessel lining, along with specific chemical signals. Both L-arginine and L-citrulline supplements target this pathway.
The nitrate-nitrite pathway. Dietary nitrate from beetroot, leafy greens, and other vegetables takes a completely different route. Bacteria on the tongue convert nitrate to nitrite; the body then converts nitrite into nitric oxide, especially under acidic or low-oxygen conditions. This pathway does not require eNOS at all — which is why it keeps working when the eNOS pathway is impaired, the very situation found in many people with cardiovascular disease.
Where L-citrulline fits. Taken by mouth, L-arginine is largely broken down in the gut and liver before it reaches the bloodstream. L-citrulline avoids that loss: after it is absorbed, the kidneys convert it into L-arginine, so it raises blood arginine levels more effectively than L-arginine taken directly. It is, in effect, a better delivery vehicle for the same raw material.
What this means. The three supplements act at different points in one system. Beetroot bypasses eNOS entirely, which is why it keeps working when the L-arginine pathway is most impaired. L-citrulline solves L-arginine’s delivery problem but still depends on a functioning eNOS. L-arginine faces the deepest obstacle of the three: it supplies raw material to an enzyme that, in cardiovascular disease, is often blocked by a separate mechanism altogether. Their evidence profiles are not interchangeable — and a safety concern with one does not automatically extend to the others.
The Clinical Evidence
Beetroot: The Most Studied Approach
Multiple trials and meta-analyses confirm that dietary nitrate from beetroot produces measurable blood pressure reductions. A 2013 meta-analysis of 16 trials found that dietary nitrate lowered systolic blood pressure by an average of 4.4 mmHg; the diastolic reduction, 1.1 mmHg, did not reach statistical significance. (1) A later randomized trial in hypertensive patients found a larger effect that held up with daily beetroot juice over four weeks — a clinic systolic reduction of roughly 8 mmHg compared with placebo — in keeping with the general pattern that the effect is larger when starting blood pressure is higher. (7) Effects peak two to three hours after consumption and persist for roughly 24 hours. (1,7) When blood pressure is already normal, the response is usually minimal.
It helps to be clear about what such a number would and would not mean. If a 4–5 mmHg systolic reduction were sustained around the clock over years, population-level data would predict a reduction in mortality on the order of 5–7%. (2) Every part of that conditional carries weight: the prediction depends on a continuous, round-the-clock exposure that beetroot has not been shown to deliver. Most beetroot trials run for days to weeks. Evidence for sustained reduction over months is limited and not uniform — some trials in treated hypertensive and older adults have found no lasting effect — and whether short-term effects translate into long-term cardiovascular protection has not been established.
One practical factor can switch beetroot’s effect off entirely: the oral microbiome. The bacteria that convert dietary nitrate to nitrite live on the tongue and in dental plaque, and antibacterial mouthwash kills them. Multiple studies have shown that the blood pressure effect of dietary nitrate disappears when these bacteria are suppressed. (1,7) Someone using antibacterial mouthwash each day while deliberately drinking beetroot juice for their blood pressure may be canceling the mechanism without realizing it. This concerns antiseptic mouthwashes specifically, not rinsing with water or using fluoride toothpaste.
L-citrulline: Smaller, Less Consistent Effects
L-citrulline’s blood pressure evidence is modest and inconsistent. A 2025 meta-analysis in middle-aged and older adults, pooling trials of L-citrulline supplements and watermelon (its main dietary source), reported small but statistically significant reductions of about 4.0 mmHg systolic and 2.5 mmHg diastolic. (8) Other meta-analyses have found no significant blood pressure effect at all. (5) Sample sizes are generally small, the results vary considerably from study to study, and cardiovascular outcome data do not exist.
Pharmacologically, L-citrulline is the more rational of the two amino acids to supplement: it raises blood arginine more effectively than L-arginine taken by mouth, because it escapes the gut and liver breakdown that limits L-arginine’s absorption. But a better delivery route does not solve the deeper problem. In cardiovascular disease, the limiting factor is rarely a shortage of raw material, as the next section explains, and L-citrulline still depends on a working eNOS. Where a blood pressure effect appears, it is small next to first-line blood pressure medications, and the evidence remains preliminary by the standard of cardiovascular outcome trials.
L-arginine: Why More Raw Material Did Not Translate Into Cardiovascular Benefit
L-arginine is the direct raw material for eNOS, which makes it the obvious supplement to try — and the reason it disappoints as a cardiovascular intervention is worth understanding, because it illustrates a pattern that recurs throughout cardiovascular supplement medicine.
Start with the biochemistry. Under normal conditions, the blood already carries far more L-arginine than eNOS can use; the enzyme is fully supplied, with raw material to spare. (6) It is not waiting for more. Adding more raw material to a system that already has a surplus does not reliably increase output.
Now add the disease context. In cardiovascular disease, a compound called ADMA — asymmetric dimethylarginine — builds up in the blood. ADMA is produced by the body itself, and it blocks nitric oxide synthase directly, no matter how much L-arginine is present. (6) So the people who would, in theory, benefit most from extra nitric oxide — those with established cardiovascular disease — are precisely the ones whose enzyme is being chemically blocked at a point beyond where extra raw material could act. Supplying more L-arginine does not remove that block.
This does not mean L-arginine has no measurable effect on blood pressure. A 2011 meta-analysis of 11 randomized trials found that oral L-arginine lowered blood pressure significantly — by about 5.4 mmHg systolic and 2.7 mmHg diastolic — but with high statistical heterogeneity, meaning the trials disagreed substantially with one another. (4) The surrogate marker moved. What it did not do was translate into clinical benefit when that was tested directly.
The safety concern matters more than the efficacy question. The VINTAGE MI trial tested L-arginine, 9 grams per day, in 153 patients recovering from a first major heart attack while on standard therapy. It was stopped early for safety: 6 patients (8.6%) in the L-arginine group died during the six-month study, compared with none in the placebo group — a statistically significant difference (P=0.01), though one based on a small number of events in a trial halted before full enrollment. (3) L-arginine also failed to improve the trial’s main measures of vascular stiffness and heart function. The investigators concluded that L-arginine should not be recommended after a heart attack. Held to the same standard this article applies to claims of benefit, a single small trial stopped early is grounds for caution, not proof of harm; the finding has been neither replicated nor refuted in the years since. But in a heart attack survivor already on proven therapy, an unresolved safety signal with no offsetting evidence of benefit is reason enough for caution — which is the basis for the investigators’ conclusion.
What this means. L-arginine lowers blood pressure in pooled trials, but that surrogate effect has not translated into cardiovascular benefit, and the one outcome trial in heart attack survivors found no benefit alongside a mortality signal. Current evidence does not support L-arginine for cardiovascular purposes — and in established cardiovascular disease, it carries a safety signal that the available evidence has not resolved.
Nitric Oxide Precursors and Cardiovascular Guidelines
No major cardiovascular guideline recommends nitric oxide precursor supplements — beetroot, L-citrulline, or L-arginine — for cardiovascular prevention or treatment.
The 2017 ACC/AHA hypertension guideline recommends specific lifestyle measures for blood pressure: more dietary potassium, less sodium, weight management, the DASH eating pattern, physical activity, and limited alcohol. (9) Beetroot juice, concentrated nitrate supplements, L-citrulline, and L-arginine are not on that list. The DASH pattern is, however, rich in the same nitrate-bearing vegetables — leafy greens, beets, and others — so nitrate from food is part of an evidence-based diet even though concentrated supplementation is not. That distinction is worth holding onto: eating nitrate-rich vegetables is established dietary guidance, while taking a supplement to deliver the same compound in isolation is a different proposition that does not carry the same evidence.
The Long-Term Evidence Gap
Across all three supplements, the same limitation applies: short-term blood pressure data exist, and cardiovascular outcome data do not.
No randomized trial has tested whether sustained beetroot consumption prevents heart attacks, strokes, or cardiovascular death. The cardiovascular benefit is inferred rather than demonstrated: beetroot lowers blood pressure, lower blood pressure reduces cardiovascular events, and therefore beetroot should reduce events. That chain of reasoning is biologically plausible — and it is exactly the kind of reasoning that cardiovascular medicine has tested before and seen fail. Niacin raised HDL cholesterol just as predicted, and did not reduce cardiovascular events. Antioxidant vitamins lowered markers of oxidative stress just as predicted, and did not reduce events. Folic acid and B vitamins lowered homocysteine just as predicted, and did not reduce events. In each case the biomarker moved in the right direction and the clinical outcomes did not follow.
This is a pattern, not a coincidence. Cardiovascular disease develops over decades through the interaction of genetics, metabolism, environment, and behavior. Changing one measurable signal with a supplement — even reliably, even reproducibly — does not necessarily change the underlying disease process. The history of biomarker interventions that failed at the outcome stage is long enough that internally consistent reasoning, on its own, is not a substitute for direct trial evidence.
That history does not prove nitric oxide precursors will fail. It does set the standard against which they should be judged — and by that standard, the evidence for long-term cardiovascular protection from any nitric oxide precursor supplement does not currently exist.
Dosing and Practical Considerations
Beetroot. Most trials use roughly 300–500 mg of dietary nitrate, equivalent to about 500 mL of beetroot juice or 200–300 grams of cooked beets. Concentrated beetroot shots and standardized powders offer more predictable dosing than whole food. Blood pressure effects peak two to three hours after consumption. The most important practical issue is the mouthwash interaction: antibacterial mouthwash kills the oral bacteria needed to convert nitrate to nitrite, and multiple studies confirm this can abolish the blood pressure effect entirely. (1,7) Rinsing with water and using fluoride toothpaste do not carry this risk.
A common and harmless side effect is beeturia — red or pink discoloration of urine and stool. It is not a sign of bleeding or kidney trouble, but it can be alarming without warning.
L-citrulline. Trials use 3–8 grams daily, usually divided across doses. It is sold as pure L-citrulline or as citrulline malate, where the malate portion does not contribute to nitric oxide effects. It is generally well tolerated. Because it can add to the effect of blood pressure medication, that combination is worth disclosing to a prescriber.
L-arginine. Given how much its effect varies across trials and the VINTAGE MI mortality signal in cardiovascular disease patients, this article does not provide dosing guidance for cardiovascular use. The evidence does not support recommending L-arginine for that purpose.
Safety
Beetroot is well tolerated. Additive low blood pressure is theoretically possible when concentrated products are combined with blood pressure medication, nitrate drugs (nitroglycerin, isosorbide), or PDE5 inhibitors — a concern more relevant with concentrated supplements than with ordinary food portions. A history of oxalate kidney stones is worth weighing, since beets are high in oxalate.
L-citrulline is well tolerated at doses up to roughly 8 grams daily. It can add to the effect of blood pressure medication, which is worth disclosing to a prescriber.
L-arginine carries the VINTAGE MI mortality signal in cardiovascular disease patients. (3) Separately, lysine and L-arginine compete for the same cellular transport routes; because lysine suppresses herpes simplex virus and arginine may favor it through that same competition, people with recurrent cold sores or genital herpes are sometimes advised to be cautious with arginine supplements — a point documented in the lysine prophylaxis literature. (11) Combined with PDE5 inhibitors (sildenafil, tadalafil, vardenafil) or nitrate medication, L-arginine can lower blood pressure more than intended; the interaction with PDE5 inhibitors specifically has been characterized in the drug interaction literature. (10)
Two Patients, Same Supplement Aisle, Different Answers
Both profiles below are composites, built from the populations studied in the trials this article reviews.
Patient A: A 54-year-old woman with stage 1 hypertension averaging 142/88 mmHg, on no medication, pursuing lifestyle change as her main strategy. She exercises regularly, is cutting back on sodium, and asks whether concentrated beetroot juice is worth adding.
She is the lowest-risk candidate for beetroot in this article: elevated blood pressure, no medication that raises a concern about additive low blood pressure, and already engaged in lifestyle change. If she adds concentrated beetroot daily, trials suggest a modest systolic reduction — on the order of a few mmHg — that daily dosing can maintain over a few weeks. (1,7) But that is an effect on a blood pressure reading, not a demonstrated reduction in her long-term cardiovascular risk: no trial has ever followed beetroot users to see whether it prevents heart attacks, strokes, or death. It is not a substitute for the lifestyle changes she is already making, and it is not a treatment for her hypertension. Whether her stage 1 hypertension is adequately managed by lifestyle alone, or needs more, is a question for her clinician rather than a supplement. If she does try beetroot, the mouthwash interaction, the two-to-three-hour timing of the peak effect, and the harmless beeturia that often follows are the practical points worth knowing.
Patient B: A 63-year-old man, eight months past a heart attack, taking aspirin, a statin, an ACE inhibitor, and a beta-blocker. He has seen an online advertisement for an “L-arginine cardiovascular support formula” and asks whether it would help restore blood flow to his heart.
He has established cardiovascular disease and is considering the one agent in this category with a documented mortality signal in exactly his population. (3) The VINTAGE MI trial was conducted in heart attack survivors on standard therapy — a close match to his situation. The current evidence does not support L-arginine in this setting, and the VINTAGE MI signal is directly relevant to him. That evidence, and any question about adjunctive cardiovascular support, belongs in a conversation with his cardiologist, who can weigh it against his full clinical picture.
Common Misconceptions
“Nitric oxide supplements are interchangeable.” They are not. Beetroot works through a pathway that stays functional in cardiovascular disease. L-arginine and L-citrulline work through eNOS, which is often impaired in exactly the people most drawn to them. Positive evidence for one does not validate the others, and their safety profiles differ substantially.
“L-arginine works because it’s the raw material the body uses.” A shortage of raw material is rarely the limiting factor. The blood already carries far more L-arginine than eNOS can use. (6) L-arginine can still lower blood pressure somewhat in trials, but in cardiovascular disease the main obstacle is ADMA — a compound that blocks the enzyme regardless of how much raw material is available — and adding more raw material does not open a pathway that is being blocked further along.
“Beetroot lowers blood pressure, so it must be protecting my heart long-term.” Lower blood pressure generally does reduce cardiovascular risk — but the link to fewer events comes from reductions sustained over years, and beetroot has mostly been studied over days to weeks. A short-term effect on a blood pressure reading is not the same as the continuous, long-term lowering that blood pressure medications provide and that outcome trials have actually tested. More to the point, cardiovascular medicine has a specific track record of interventions that moved blood pressure and other biomarkers exactly as predicted, then failed to reduce cardiovascular events when the direct question was asked. That gap has not been tested for nitric oxide precursors, so it cannot yet be assumed to have been closed.
“Antibacterial mouthwash has nothing to do with supplements.” It eliminates the oral bacteria that are the first step in beetroot’s blood pressure mechanism. The effect is not subtle: multiple studies show the blood pressure reduction from dietary nitrate disappears when those bacteria are suppressed. (1,7)
“L-arginine is safe because it is a natural amino acid.” L-arginine is found in dietary protein. But as a concentrated supplement in cardiovascular disease patients, it is the agent for which the VINTAGE MI trial documented a mortality signal that later evidence has not resolved. (3) Natural origin and ordinary presence in food do not establish the safety of supplemental doses in high-risk clinical populations.
The Bottom Line
Beetroot produces short-term blood pressure reductions in randomized trials. L-citrulline shows smaller, less consistent effects. The biology is understood, the short-term physiology is reproducible, and the mouthwash interaction is the practical detail most users have never heard of. What none of these supplements has demonstrated is a reduction in heart attacks, strokes, or cardiovascular death — and that gap is not a regulatory technicality. It is the question that cardiovascular medicine has learned, again and again, cannot be answered by biomarker data alone.
Nitric oxide precursors are neither validated cardiovascular therapies nor implausible ones. They sit in an honest middle position: plausible mechanisms, real short-term physiology, and an outcome question that has not been answered. For someone with elevated blood pressure pursuing lifestyle change, eating more nitrate-rich vegetables is part of established dietary guidance; concentrated beetroot may add a modest, short-term blood pressure effect, but with no evidence that it changes long-term outcomes. For someone on blood pressure medication or with established cardiovascular disease, the wider evidence — including the VINTAGE MI signal with L-arginine — is information a prescribing physician would want to have.
The distinction that matters most is between a supplement that improves a measurement and a therapy that reduces events. For nitric oxide precursors, the first has been demonstrated. The second has not.
Article 13 turns to berberine — a supplement with pharmaceutical-level metabolic effects, pharmaceutical-level drug interaction risks, and no cardiovascular outcome data to resolve the tension between them.
Key Terms
ADMA (asymmetric dimethylarginine): A compound the body produces that blocks nitric oxide synthase and accumulates in cardiovascular disease. Because it blocks the enzyme regardless of how much L-arginine is present, it is a key reason raw-material supplementation fails in the patients who would, in theory, need it most.
Beeturia: Red or pink discoloration of urine and stool after eating beets. Harmless and unrelated to kidney function, but common enough to anticipate.
Dietary nitrate: Nitrate compounds found in beetroot, leafy greens, and other vegetables. Converted to nitric oxide through the nitrate-nitrite pathway, an eNOS-independent route that stays active in cardiovascular disease.
eNOS (endothelial nitric oxide synthase): The enzyme in blood vessel lining cells that converts L-arginine into nitric oxide. In most cardiovascular disease, the limiting factor is impaired function of this enzyme — not a shortage of raw material.
Endothelial dysfunction: Impaired function of the blood vessel lining, marked by reduced nitric oxide production and increased vascular inflammation. An early feature of atherosclerosis, often detectable years before clinical events.
L-arginine: An amino acid and the direct raw material for eNOS. Supplementation lowers blood pressure with wide variation across trials, has not demonstrated cardiovascular outcome benefit, and carries a safety signal in patients with established cardiovascular disease.
L-citrulline: An amino acid converted to L-arginine in the kidneys, bypassing the gut and liver breakdown that limits oral L-arginine’s absorption. Shows small, inconsistent blood pressure effects in randomized trials.
Nitrate-nitrite pathway: The route by which dietary nitrate becomes nitric oxide, starting with oral bacteria converting nitrate to nitrite in the mouth. It works independently of eNOS and stays active when the L-arginine–eNOS pathway is impaired.
PDE5 inhibitors: Phosphodiesterase-5 inhibitors, including sildenafil (Viagra), tadalafil (Cialis), and vardenafil. Used for erectile dysfunction and pulmonary hypertension. Combined with nitric oxide precursors — particularly L-arginine — they can lower blood pressure more than intended.
VINTAGE MI: The Vascular Interaction With Age in Myocardial Infarction trial. It tested L-arginine in 153 heart attack survivors on standard therapy and was stopped early after 6 deaths (8.6%) in the L-arginine group versus none on placebo (P=0.01). The principal safety signal for this agent in cardiovascular populations.
References
- Siervo M, Lara J, Ogbonmwan I, Mathers JC. Inorganic nitrate and beetroot juice supplementation reduces blood pressure in adults: a systematic review and meta-analysis. J Nutr. 2013;143(6):818–826.
- Ettehad D, Emdin CA, Kiran A, et al. Blood pressure lowering for prevention of cardiovascular disease and death: a systematic review and meta-analysis. Lancet. 2016;387(10022):957–967.
- Schulman SP, Becker LC, Kass DA, et al. L-arginine therapy in acute myocardial infarction: the Vascular Interaction With Age in Myocardial Infarction (VINTAGE MI) randomized clinical trial. JAMA. 2006;295(1):58–64.
- Dong JY, Qin LQ, Zhang Z, et al. Effect of oral L-arginine supplementation on blood pressure: a meta-analysis of randomized, double-blind, placebo-controlled trials. Am Heart J. 2011;162(6):959–965.
- Mirenayat MS, Moradi S, Mohammadi H, Rouhani MH. Effect of L-citrulline supplementation on blood pressure: a systematic review and meta-analysis of clinical trials. Curr Hypertens Rep. 2018;20(11):98.
- Allerton TD, Proctor DN, Stephens JM, et al. L-citrulline supplementation: impact on cardiometabolic health. Nutrients. 2018;10(7):921.
- Kapil V, Khambata RS, Robertson A, Caulfield MJ, Ahluwalia A. Dietary nitrate provides sustained blood pressure lowering in hypertensive patients: a randomized, phase 2, double-blind, placebo-controlled study. Hypertension. 2015;65(2):320–327.
- Luo P, Chen J, Liu K, Zhang J. Does L-citrulline supplementation and watermelon intake reduce blood pressure in middle-aged and older adults? A systematic review and meta-analysis of randomized controlled trials. Clin Nutr ESPEN. 2025;69:653–664.
- Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults. J Am Coll Cardiol. 2018;71(19):e127–e248.
- Schwartz BG, Kloner RA. Drug interactions with phosphodiesterase-5 inhibitors used for the treatment of erectile dysfunction or pulmonary hypertension. Circulation. 2010;122(1):88–95.
- Mailoo VJ, Rampes S. Lysine for herpes simplex prophylaxis: a review of the evidence. Integr Med (Encinitas). 2017;16(3):42–46.
HeartBuddi • Your heart. Own it.