The Claim

Oral citrulline supplementation at 0.18 g/kg/day for 7 days increases plasma citrulline concentration by 17-fold and plasma arginine concentration by 3-fold in adults with short bowel syndrome and residual small bowel of approximately 90 cm, without altering whole-body protein synthesis in those with near-normal baseline levels.

Source: Effect of oral citrulline supplementation on whole body protein metabolism in adult patients with short bowel syndrome: A pilot, randomized, double-blind, cross-over study.

What the research says

Supports is higher

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

Supports
58score
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.

Quantitative
1 study reviewed
In plain English

In adults with short bowel syndrome and about 90 cm of remaining small intestine, taking 0.18 grams of citrulline per kilogram of body weight daily for 7 days raises plasma citrulline levels 17 times and plasma arginine levels 3 times, without changing overall protein synthesis rates.

See the scientific wording

Oral citrulline supplementation at 0.18 g/kg/day for 7 days increases plasma citrulline concentration by 17-fold and plasma arginine concentration by 3-fold in adults with short bowel syndrome and residual small bowel of approximately 90 cm, indicating enhanced bioavailability of these amino acids without altering whole-body protein synthesis in those with near-normal baseline levels.

Why this might work

When citrulline is taken by mouth, it is absorbed directly through the small intestine and travels to the liver, where it is changed into arginine. This process increases the amount of citrulline and arginine in the blood without affecting how the body builds proteins.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Effect of oral citrulline supplementation on whole body protein metabolism in adult patients with short bowel syndrome: A pilot, randomized, double-blind, cross-over study.

    Taking citrulline pills for a week greatly increased citrulline and arginine in the blood of people with short bowel syndrome, just like the claim says. It also didn’t change how their bodies built protein — as long as their citrulline levels were already normal.

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.