L-Citrulline
TL;DR
Amino acid that converts to L-arginine, then to nitric oxide. More effective at raising arginine levels than arginine supplementation itself (better oral bioavailability). Supports blood vessel health.
Safety: Excellent. Very well-tolerated. No significant adverse effects at standard doses.
Cost: approximately $12-18/month.
Best for: Heart disease
What the research says
Multiple trials show improved endothelial function and blood pressure. More effective at raising arginine than arginine itself. Also improves exercise performance.
L-Citrulline on Amazon
*Link is just for your convenience - we do not make any fees
Safety & practical info
Very well-tolerated. No significant adverse effects at standard doses.
Additive blood pressure lowering effects. Caution with antihypertensives.
Affordable. Available as pure L-citrulline or citrulline malate.
Sources for this page include published meta-analyses, systematic reviews, and NIH dietary supplement fact sheets. All claims reflect the evidence as of early 2026.
This is not medical advice. Consult your healthcare provider before starting any supplement, especially if you take medications.