The Claim
Oral supplementation with 1 gram of L-citrulline and 1 gram of L-arginine combined increases plasma L-arginine levels more effectively than 2 grams of either amino acid alone in healthy Japanese males aged 20–49, as demonstrated by a 25% higher area under the curve (AUC0–1h) and peak concentration at 1 hour post-ingestion.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
In healthy Japanese men aged 20–49, taking 1 gram of L-citrulline and 1 gram of L-arginine together raises plasma L-arginine levels more than taking 2 grams of either amino acid separately, with a 25% higher area under the curve and higher peak concentration at one hour after ingestion.
See the scientific wording
Oral supplementation with 1 gram of L-citrulline and 1 gram of L-arginine combined increases plasma L-arginine levels more effectively than 2 grams of either amino acid alone in healthy Japanese males aged 20–49, as demonstrated by a 25% higher area under the curve (AUC0–1h) and peak concentration at 1 hour post-ingestion in a randomized controlled trial of 42 participants.
When L-citrulline is taken by mouth, it enters the bloodstream without being broken down quickly. It blocks an enzyme that normally destroys L-arginine, so more L-arginine from the supplement stays in the blood. This lets L-arginine levels rise higher and last longer than when taking L-arginine alone.
What the research says
1 studyTaking 1 gram of L-citrulline and 1 gram of L-arginine together boosts blood levels of L-arginine better than taking 2 grams of just one of them, and this study shows that’s true.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.