The Claim

Oral administration of a combination of L-citrulline and L-arginine at half-dose each rapidly increases plasma L-arginine concentration and elevates plasma nitric oxide metabolites (NOx) and cyclic GMP in rats and rabbits, indicating enhanced nitric oxide bioavailability within hours of ingestion.

Source: Oral supplementation with a combination of L-citrulline and L-arginine rapidly increases plasma L-arginine concentration and enhances NO bioavailability.

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
13score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

How it works
1 study reviewed
In plain English

Oral intake of equal halves of L-citrulline and L-arginine increases plasma L-arginine levels and raises nitric oxide metabolites and cyclic GMP in rats and rabbits within hours.

See the scientific wording

Oral administration of a combination of L-citrulline and L-arginine at half-dose each rapidly increases plasma L-arginine concentration and elevates plasma nitric oxide metabolites (NOx) and cyclic GMP in rats and rabbits, indicating enhanced nitric oxide bioavailability within hours of ingestion.

Why this might work

When L-citrulline and L-arginine are taken together by mouth, the body converts L-citrulline into more L-arginine in the kidneys, which raises the amount of L-arginine in the blood. This extra L-arginine feeds into blood vessel cells, where it is turned into nitric oxide. Nitric oxide then signals nearby muscle cells in the blood vessel walls to relax by increasing a chemical called cyclic GMP, which causes the vessels to widen and blood flow to increase.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Oral supplementation with a combination of L-citrulline and L-arginine rapidly increases plasma L-arginine concentration and enhances NO bioavailability.

    Taking L-citrulline and L-arginine together by mouth quickly boosts a key chemical in the blood that helps blood vessels relax, and this study in rats and rabbits proves it works fast.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.