Amino acids
L-Arginine
Nitric oxide
Nitric oxide precursor; vasodilation, blood flow. Common dose 3–6 g/day.
What L-Arginine does
L-Arginine is the substrate for nitric oxide synthase, which produces NO — the primary endothelial vasodilator. Oral arginine raises plasma arginine but its effect on NO is blunted by intestinal and liver metabolism (first-pass arginase). Citrulline supplementation often raises plasma arginine more effectively than arginine itself. Clinical-trial evidence is mixed for blood-flow and exercise outcomes; arginine has stronger evidence in clinical situations like erectile dysfunction (5 g/day) and pre-eclampsia prevention than for general performance.
Food sources of L-Arginine
Approximate L-Arginine content per serving. Whole-food intake counts toward your daily total alongside any supplemental dose.
| Food | Serving | L-Arginine |
|---|---|---|
| Pumpkin seeds | 1 oz | 1.4 g |
| Cooked turkey | 3 oz | 2 g |
| Cooked chicken breast | 3 oz | 1.9 g |
| Cooked salmon | 3 oz | 1.5 g |
| Lentils (cooked) | 1 cup | 1.3 g |
| Peanuts | 1 oz | 0.9 g |
Signs of L-Arginine deficiency
- ●Conditionally essential — adults rarely become deficient on a normal protein intake
- ●Inherited urea cycle disorders cause arginine deficiency with hyperammonemia
Who needs more L-Arginine
Groups and situations where L-Arginine requirements rise or status commonly runs low:
- ●Erectile dysfunction (5 g/day, modest effect)
- ●Pre-eclampsia prevention (under obstetric guidance)
- ●Wound healing and post-surgical recovery (clinical trials use 6–12 g)
- ●Severely catabolic states (burns, sepsis — clinical use)
How L-Arginine appears on labels
Supplement labels list L-Arginine under several names depending on the chemical form used. Any of these on an ingredients panel counts toward your L-Arginine intake:
- l-arginine
- arginine
Best supplements for L-Arginine
Top-scoring supplements in our catalog that list L-Arginine on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.
Deep dive
For mechanism of action, dosing protocols, evidence grade, and interaction warnings on L-Arginine, see the full encyclopedia entry:
L-Arginine encyclopedia entry →Research on L-Arginine
Peer-reviewed studies in our research database that reference L-Arginine. Each entry links to a detailed methodology review.
Frequently asked questions
What is the daily target for L-Arginine?
What foods are highest in L-Arginine?
What is the best form of L-Arginine to supplement?
What are the signs of L-Arginine deficiency?
Who is most at risk for low L-Arginine?
Related amino acids
Track your full intake
Formulate's free web app aggregates L-Arginine (and ~40 other nutrients) across every supplement in your stack — flagging underdoses, overlaps, and upper-limit overshoots in one view.
Track your intake free →Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Targets and upper limits are general adult reference values; individual needs vary by age, sex, pregnancy status, and clinical context.