The Claim

The absence of flow-mediated dilation improvement following citrulline malate supplementation in healthy young males is associated with larger baseline brachial artery diameter, indicating that vascular adaptation in physically active individuals limits acute vasodilatory responses.

Source: Acute effect of citrulline malate on flow-mediated dilation and serum pharmacodynamics in healthy young males

What the research says

Supports is higher

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

Supports
68score
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 healthy young men who exercise regularly, citrulline malate does not improve blood vessel dilation because their arteries are already larger and less responsive to vasodilatory stimuli.

See the scientific wording

The absence of flow-mediated dilation improvement after citrulline malate in healthy young males may reflect physiological ceiling effects, as larger baseline brachial artery diameter is associated with reduced FMD responsiveness, suggesting vascular adaptation in active individuals limits acute vasodilatory potential.

Why this might work

In people with naturally larger arteries from regular physical activity, the blood vessels are already stretched to their maximum relaxed state, so even when more nitric oxide is made, the arteries cannot expand further.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Acute effect of citrulline malate on flow-mediated dilation and serum pharmacodynamics in healthy young males

    In healthy, active guys, taking citrulline malate boosts certain blood chemicals, but their arteries don’t get any more dilated — probably because they’re already in great shape and their blood vessels can’t respond much more.

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.