Supplement evidence

103 / 575Performance

L-arginine

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The short answer

Can raise nitric-oxide substrate but oral bioavailability and exercise results are inconsistent.

Evidence and scope: Mixed evidence
This status does not grade the ingredient for every goal, outcome, or person.
Important limitation: Trials are inconsistent or small, so a reliable clinically important benefit is not established.
Before deciding: Key concern: Avoid after recent myocardial infarction; review nitrates, PDE5 inhibitors, blood-pressure drugs, herpes, asthma, and kidney disease.

01 / PRACTICAL GUIDE

Dose, absorption, and combinations

These are indication-specific reference or studied ranges—not a personalized prescription. Start with the objective, then check the form, label, medicines, and health conditions.

Reference range by objective

Sports performance3–6 g before exercise; larger doses often cause GI symptoms

Reference or studied range—not a personalized prescription. The product label or a clinician may specify a different dose.

Dose source ↗

More is not automatically better. A clinician or product label may specify a different amount.

Absorption / solubilityWater-soluble

Water-soluble or readily water-dispersible. This does not mean excess is always harmless.

How it is commonly taken

Divide or take away from heavy meals if tolerated.

Do not combine casually

Avoid after recent myocardial infarction; review nitrates, PDE5 inhibitors, blood-pressure drugs, herpes, asthma, and kidney disease.

Dose and use source ↗

Dose and use links lead to primary or official source material. Search links are discovery tools, not proof that every returned paper applies.

02 / EVIDENCE

What the research says

We keep supportive, mixed, negative, safety, and contextual findings together. The headline never replaces the underlying papers.

2research papers in this ledger

23unique primary studies represented

153unique participants represented

These are audited counts for this JIVANA collection, not search-result totals. Participants are counted once when multiple papers use the same cohort; review papers are not added again to participant totals.

Open the research timelineResearch timeline

Entries are ordered by publication year. A study period appears only when the source reports it.

2022

Mixed or qualifiedPMID 34967840 · PROSPERO CRD42021242772

L-arginine supplementation and blood pressure in adults

Pooled blood pressure fell by about 6.4/2.6 mmHg, but effects disappeared in trials longer than 24 days and at doses above 9 g/day. Short heterogeneous surrogate-outcome trials do not establish durable cardiovascular benefit.

Published: 202222 primary studies represented

Study design and methods

Design: Systematic review and dose-response meta-analysis of 22 randomized placebo-controlled trials
Population: Adults with and without hypertension across short trials; the abstract did not report a participant total
Intervention: Oral L-arginine for at least 4 days versus placebo
Outcome: Systolic and diastolic blood pressure

Open research record ↗

2006

Safety signalPMID 16391217 · NCT00051376

L-arginine after acute myocardial infarction

L-arginine did not improve vascular stiffness or ejection fraction. Six participants taking L-arginine died versus none on placebo, prompting early closure; it should not be used after acute myocardial infarction.

Published: 2006Duration: Planned 6 months; enrollment stopped early for safetyn=153 participants

Study design and methods

Design: Randomized, double-blind, placebo-controlled clinical trial
Population: 153 adults after a first ST-elevation myocardial infarction
Intervention: L-arginine with a goal of 3 g three times daily plus standard therapy versus placebo
Outcome: Vascular stiffness, ejection fraction, clinical events, and mortality

Open research record ↗

Unscreened discovery appendix—not evidence61 candidate publicationsSearch run: Aug 21, 2026

Complete for the displayed PubMed query at the search timestamp—not for all databases or every possible synonym. Candidates can be irrelevant, duplicate the same study, or report negative findings. They are never summed as evidence or participants until screened.

03 / SOURCES

Start with the source material

Official evidence overviewPubMed bounded human-evidence search Live PubMed discovery searchNational Library of Medicine

The live search is for discovery only. Search-result counts change and are not included in the audited totals above.

Recent PubMed discovery recordsDirect links to the first 12 records returned by the reproducible search. These are discovery candidates—not reviewed summaries or a count of supportive findings.

04 / EXPERT CONTEXT

Expert context—not evidence

Expert positions are dated context—not scientific evidence. They never raise the evidence status or become consensus by repetition.

No direct, source-verified endorsement is currently recorded. Research authorship or discussion alone is not treated as endorsement.