The Claim

Oral supplementation with L-citrulline and L-arginine rapidly increases plasma L-arginine concentration in rats and rabbits, and the combination of both amino acids produces a greater increase than either amino acid administered alone.

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.

Cause and effect
1 study reviewed
In plain English

When rats and rabbits are given L-citrulline and L-arginine by mouth, their blood levels of L-arginine rise quickly, and giving both amino acids together raises blood L-arginine more than giving either one by itself.

See the scientific wording

Oral L-citrulline and L-arginine supplementation rapidly elevates plasma L-arginine concentration in rats and rabbits, with the combination producing a more pronounced effect than either amino acid administered alone.

Why this might work

When taken by mouth, L-citrulline is absorbed and turned into L-arginine in the kidneys, while L-arginine is absorbed directly into the blood. Together, they flood the bloodstream with more L-arginine than either one alone, because they use two different paths to get there and neither blocks the other.

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.

    When rats and rabbits took both L-citrulline and L-arginine together, their blood levels of L-arginine went up more than when they took just one of them. So, combining them works better than using either alone.

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

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