An amino acid studied for its role in nitric oxide production and blood flow.
L-Citrulline is an amino acid the body converts into L-arginine and then nitric oxide, a molecule involved in relaxing and widening blood vessels.
It's one of the more research-backed ingredients in the men's performance category, with studies looking at its effect on blood flow and exercise performance.
We don't have a Supplement Facts label confirming the exact amount in HorseFil, so we can't say whether it's dosed at levels comparable to clinical research.