Arginine
L-Arginine is a conditionally essential amino acid and the primary precursor to nitric oxide (NO). C-grade evidence for blood flow improvement and anaerobic capacity. IMPORTANT: Oral arginine has poor bioavailability due to extensive first-pass metabolism in the gut (arginase). Citrulline is actually MORE effective at raising plasma arginine levels. Common in pre-workout supplements for 'pumps' but evidence for performance benefits is modest. May help with erectile dysfunction in mild cases (C-grade) and blood pressure.
Quick Answer
What it is
L-Arginine is a conditionally essential amino acid and the primary precursor to nitric oxide (NO). C-grade evidence for blood flow improvement and anaerobic capacity.
Key findings
- Grade C: Blood Flow
- Grade C: Anaerobic Capacity (General Athletic Performance)
- Grade C: Adiponectin (Type 2 Diabetes)
Safety
No specific caution or interaction language was detected in the current summary/outcome notes.
ℹ️ Quick Facts: Arginine
Quick Facts: Arginine
- Best Evidence:Grade C
- Conditions Studied:13
- Research Outcomes:80
- Key Effect:General Athletic Performance
Detailed Outcomes
Evidence by Condition
Best grade per condition (each condition may have multiple outcomes)
Research Citations (17)
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