The Claim

Oral supplementation with half-doses of L-citrulline and L-arginine together produces a greater increase in plasma nitric oxide metabolites and cyclic GMP than full-dose supplementation of either amino acid alone in rats and rabbits.

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

In rats and rabbits, giving half the usual amount of both L-citrulline and L-arginine together increases plasma nitric oxide metabolites and cyclic GMP more than giving the full amount of either one alone.

See the scientific wording

In rats and rabbits, oral supplementation with L-citrulline and L-arginine at half-dose each produces a greater increase in plasma nitric oxide metabolites (NOx) and cyclic GMP than either amino acid alone at full dose.

Why this might work

When both L-citrulline and L-arginine are taken together, the body converts L-citrulline into more L-arginine in the kidneys, which floods the bloodstream with the raw material needed to make nitric oxide. This extra L-arginine lets blood vessel cells produce more nitric oxide, which then triggers a chain reaction that increases cyclic GMP, leading to wider blood vessels and better blood flow.

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.

    Giving rats and rabbits half the usual amount of both L-citrulline and L-arginine together made their bodies produce more nitric oxide-related molecules than giving them the full amount of just one of them alone.

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

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